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Efficiently constructing structures with high thermal stability is a key objective in the development of energetic compounds. However, the existing synthesis processes for heat‐resistant energetic materials are frequently hampered by their complexity and low yields. This study presents a significant breakthrough in addressing these challenges. It successfully synthesizes 4‐amino‐5‐(3‐amino‐1H‐pyrazole‐4‐yl)‐2,4‐dihydro‐3H‐1,2,4‐triazol‐3‐one (APTO) using a streamlined two‐step process, achieving an impressive high yield of 87.5 %. The structure was determined through X‐ray single crystal diffraction analysis, revealing a nearly planar intramolecular structure. Hirshfeld surface analysis, weak interaction analysis, and aromaticity analysis were conducted, illustrating a substantial presence of hydrogen bonds and π ‐ π stacking interactions within and between molecules. These interactions contribute significantly to exceptional thermal stability of ATPO. Furthermore, the thermal stability of ATPO was confirmed through DSC analysis, exhibiting a decomposition temperature as high as 365.2°C. This temperature surpasses that of the heat‐resistant explosive HNS (325°C), further validating its excellent thermal stability. The construction of this conjugated structure offers valuable guidance for the future structural design of heat‐resistant energetic materials. It opens up possibilities for the development of novel compounds with improved thermal stability based on similar conjugated architectures. [ABSTRACT FROM AUTHOR]

A quinoline-containing semi-salamo-type ligand, HL, was synthesized and a dinuclear Ni(II) complex, [Ni2(L)2(NCS)2], was produced. The complex was experimentally analyzed by elemental analysis, fluorescence, and UV–Vis spectroscopy. X-ray single crystal diffraction experiments showed that the complex is a six-coordinate, structurally symmetric, phenoxy-bridged dinuclear Ni(II) dimer with the participation of SCN− in the coordination to satisfy charge neutrality. The self-assembly forms a 2-D supramolecular network structure through hydrogen bonding and π⋯π interactions. DFT calculations were performed on the complex to analyze its energy gaps, and UV–Vis experiment was verified by TD-DFT calculation. In addition, close intermolecular contacts were investigated by Hirshfeld surface analysis to quantify the crystal structure interaction. [ABSTRACT FROM AUTHOR]

Centrosymmetric homopolynuclear Cu(II) and Co(II) chelated complexes, [Cu2(L)(H2O)2] (1) and [Co4(L)(μ-OAc)2(CH3OH)4(OAC)2]⋅2CH2Cl2 (2), were synthesized using a new symmetrical methoxy-disubstituted bis(salamo)-type ligand, H4L, with Cu(II) and Co(II) salts in organic solvents. Complexes 1 and 2 were structurally characterized by single-crystal X-ray crystallography. The results indicated that 1 is a five-coordinate dinuclear structure containing Cu(II) and 2 is a tetranuclear Co(II) complex with two distinct six-coordinate environments. Furthermore, 1 and 2 pack into three-dimensional and two-dimensional extended networks, respectively. The UV–Vis spectra, IR spectra, and Hirshfeld surface analyses of the complexes were carried out to further characterize the coordination between H4L and the metal(II) ions. Fluorescence methods were used to interrogate the coordination, where changes in emission with varied amounts of ligand supported solution-phase coordination ratios of H4L with Cu(II) ion of 1:2 and with Co(II) ion of 1:4, respectively. [ABSTRACT FROM AUTHOR]

A penta-coordinated dinuclear Zn(II) complex, [Zn2(L)(μ-PhCOO)(EtOH)] (1), and a hexa-coordinate tetranuclear Cd(II) complex, [{Cd2(L)(EtOH)(η-OAc)}2]·2CH2Cl2 (2), have been synthesized by reactions of a single-armed salamo-based ligand, H3L, and two kinds of transition metal salts, (Zn(NO3)2·6H2O and Cd(OAc)2·2H2O), respectively. Complexes 1 and 2 have been characterized by elemental analyses, single crystal X-ray diffraction, IR spectra and UV-Vis spectra. Complex 1 is composed of a totally deprotonated ligand (L)3- moiety, two Zn(II) ions, one μ-PhCOO- counter-anion and one coordinated ethanol molecule. The (L)3- unit packages two Zn(II) ions, the μ-PhCOO- counter-anion bridges two adjacent Zn(II) ions and one ethanol molecule coordinates with the Zn2 ion, so that both Zn(II) ions are penta-coordinated with slightly distorted trigonal bipyramidal configurations, and the τ5 values of Zn1 and Zn2 are 0.86 and 0.65, respectively. Complex 2 consists of two discrete and similar electroneutral tetra-nuclear units, 2 A and 2B, and two crystallized dichloromethane molecules. Each unit has a symmetric structure that is made up of two completely deprotonated ligand (L)3- moieties, four Cd(II) ions, two η-OAc- counter-anions and two coordinated ethanol molecules. Fluorescence properties and Hirshfeld surfaces analyses have been studied as well. [ABSTRACT FROM AUTHOR]

The coordination behaviors of asymmetric quinoline-decorated half-salamo-type ligand HL1 with Cu(NO3)2·3H2O and Cu(OAc)2·H2O were studied. Two Cu(II) complexes, [Cu(L1)(NO3)]·CH3CH2OH (1) and [Cu2(L2)2] (2), were isolated and characterized by X-ray crystallography, FTIR, UV–vis, and fluorescence spectroscopies. Structural analyses showed that 1 is a mononuclear species, whereas 2 is a binuclear entity. Spontaneous cleavage along the oxime N-O bond close to quinoline ring of the ligand HL1 occurred upon reaction with Cu(OAc)2·H2O, yielding an unexpected complex 2. Moreover, DFT theoretical calculations and Hirshfeld surfaces analyses of the ligand HL1 and its corresponding Cu(II) complexes were investigated in detail. [ABSTRACT FROM AUTHOR]

Two structurally different Cu(II) and Co(II) complexes, [Cu(L)] (1) and [Co2(L)2]⋅2CH3OH (2), constructed from a new polyhalogen-substituted unsymmetric salamo-based ligand (H2L, 4-chloro-4′-bromo-6-bromo-6′-tert-butyl-2,2′-[ethylenedioxybis(nitrilomethylidyne)]diphenol) were synthesized by wet-chemical methods. Complexes 1 and 2 were characterized through elemental analyses, IR and UV-vis spectroscopies and single crystal X-ray crystallography. In addition, the differences of the structures, electronic absorption characteristics and fluorescence property transitions from the ligand to complexes 1 and 2 were studied. The largest difference is that the ligand H2L can react with M(OAc)2 (M = Cu(II) and Co(II)) to give two complexes with distinct structures and behaviors. There are two chemically identical but crystallographically independent structural units (molecules A and B) in 1. Moreover, each Cu(II) ion (Cu1 or Cu2) is four-coordinate and possesses a square planar geometry, but both Co(II) ions of 2 are bridged by phenoxide ions and possess five-coordinate trigonal bipyramidal configurations. At the same time, Hirshfeld surface analyses showed there are short-range interaction features from the ligand to complexes 1 and 2, the O···H/H···O interactions of the ligand are significantly stronger than those of 1 and 2. [ABSTRACT FROM AUTHOR]

A relatively rigid acyclic salamo-type ligand H2L and its square planar Cu(II) complex, [Cu(L)]·CH3OH, were synthesized and characterized by X-ray crystallography, as well as Fourier-transform infrared spectra, UV–Vis spectra, Hirshfeld surface analyses and DFT calculations. The ligand crystallizes in monoclinic space group P 21/c and has pairs of intramolecular hydrogen bonds between the oxime nitrogen atoms and the hydroxyl groups. The Cu(II) complex crystallizes in the monoclinic space group P 21/c. The Cu(II) ion is located in the N2O2 cavity of the fully deprotonated salamo-type ligand (L)2− unit, thus forming a four-coordinate distorted square planar geometry. At the same time, a belt-like, 2-D supramolecular structure is formed by the interaction of intermolecular hydrogen bonds, and the intermolecular interaction force is quantitatively analyzed by Hirshfeld surfaces. Significantly, fluorescence properties of the ligand and its Cu(II) complex were also studied. The coordination ratio of the Cu(II) complex was proved by UV–Vis and fluorescence titration experiments. [ABSTRACT FROM AUTHOR]

d-Block transition metal(II)-lanthanide(III) (3d-4f) hetero‐trinuclear [Cu(II)2Ln(III)] (Ln = La and Ce) complexes [Cu2La(L)(ƞ2-NO3)3(CH3OH)2]·2CH3OH (1) and [Cu2Ce(L)(ƞ2-NO3)3(CH3OH)2]·2CH3OH (2) are described, both of which are formed by a flexible symmetrical bis(salamo)-type ligand H4L. The two 3d-4f complexes have been synthesized and characterized by elemental analyses, IR spectra and UV–Vis spectroscopy. The crystal structures of 1 and 2 were determined by single-crystal X-ray diffraction analyses. In 1 and 2, each Cu(II) ion (Cu1 or Cu2) is located in the N2O2 cavity of an (L)4− unit, while the apex is occupied by one oxygen atom of the coordinated methanol molecule, forming a penta-coordinated square pyramidal geometry. The lanthanide(III) (La or Ce) ion is located in the O6-donor coordination sphere of the completely deprotonated (L)4− unit and coordinated with the other six oxygen atoms of the three nitrate ligands to form a twelve-coordinated icosahedron. At the same time, the supramolecular structures are formed by intermolecular hydrogen bonding interactions and quantitatively determined by Hirshfeld surfaces analyses. Fluorescence properties and DFT calculations of 1 and 2 were also studied. [ABSTRACT FROM AUTHOR]

Two novel homomultinuclear complexes [Co6(L)2(μ‐OAc)4]·2CHCl3·CH3COCH3 (1) and [Ni2(L)(H2O)2(Py)2]·2CHCl3 (2) with a newly designed rigid bis(salamo)‐type tetraoxime ligand (H4L) were synthesized and characterized by elemental analyses, Fourier transform infrared (FT‐IR) spectra, UV–Vis absorption spectra, and X‐ray single‐crystal diffractions. Complex 1 is a novel triple‐decker symmetrical six‐core cluster structure with twofold axis and inversion center. The Co(II) atoms were sandwiched between the bis(salamo)‐type ligands and possess two different geometries of distorted tetragonal pyramid and octahedron, respectively. Complex 2 possesses a dinuclear structure and the Ni(II) atoms are located in the N2O2 cavities of the ligand, and axial coordination atoms come from the coordinated water and pyridine molecules. Both Ni(II) atoms adopt distorted octahedral geometries. The interactions were quantitatively determined by Hirshfeld surfaces analyses of complexes 1 and 2. The coordination ratios were determined by studying the fluorescence properties of complexes 1 and 2. The results of fluorescence titration experiment show that the metals to ligand binding ratios are 6:2 and 2:1 for complexes 1 and 2, respectively. [ABSTRACT FROM AUTHOR]

Two dinuclear Ni (II) and Zn (II) salamo‐type complexes, [Ni2(L)(μ‐OAc)(MeOH)]·2CHCl3 (1) and [{Zn2(L)(μ‐OMe)}3]·3CHCl3·MeOH (2), have been successfully synthesized by wet‐chemical method and characterized by elemental analyses, IR spectra, UV–Vis spectra and single crystal X‐ray diffraction. Complex 1 consists of two closely related dinuclear units 1A and 1B, and complex 2 consists of three closely related dinuclear units 2A, 2B and 2C. The five units are unique example of crystallographically independent but chemically identical molecules. The Ni (II) atoms of complex 1 are located in the N2O4 coordination cavities, possessing six‐coordinated distorted octahedral geometries, but all Zn (II) atoms in complex 2 are located in the N2O3 coordination cavities, possessing five‐coordinated distorted square‐pyramid and triangular bipyramid geometries, the geometries about the Zn (II) atoms (Zn3 and Zn6) that obtain in 2B and 2C where τ5 is very close to 0.500, which is τ5Zn3 = 0.5006 and τ5Zn6 = 0.4941, respectively. The interactions were quantitatively determined by Hirshfeld surfaces analyses. Significantly, fluorescence properties were also investigated. [ABSTRACT FROM AUTHOR]

A new salamo-based ligand and its two new dinuclear complexes [{Co(L)}2(4,4′-bipy)] (1) and [{Cu(L)}2] (2), were designed and self-assembled, and characterized by elemental analyses, FT-IR, UV–vis absorption spectroscopy and X-ray crystallography. In 1, two [Co(L)] units are bridged by the auxiliary bidentate ligand 4,4′-bipy with nitrogen-donor atoms to form a centrosymmetric dimeric structure. Both Co(II) ions are five-coordinate and possess distorted trigonal bipyramidal configurations. Complex 2 is composed of two Cu(II) ions and two completely deprotonated ligand (L)2– units. Interestingly, the two [Cu(L)] units form a dimer bridged by two oxime O atoms. This structure is rare in reported salamo-based Cu(II) complexes. Both Cu(II) ions are five-coordinate and possess distorted tetragonal pyramidal geometries. Hirshfeld surface analyses showed that the O–H/H–O interactions of 1 and 2 are weaker than that of H2L. This phenomenon indicates that H2L forms corresponding complexes with the Co(II) and Cu(II) ions through the deprotonation of phenolic hydroxyl groups. The fluorescence spectra showed that the fluorescence of the ligand is almost completely quenched due to the coordination of the Cu(II) ions with H2L. DFT calculations show that 1 and 2 have higher chemical stability than that of H2L. [ABSTRACT FROM AUTHOR]

Three novel multinuclear NiII complexes, namely, bis{μ‐2‐methoxy‐6‐[8‐(pyridin‐2‐yl)‐3,6‐dioxa‐2,7‐diazaocta‐1,7‐dien‐1‐yl]phenolato}bis[thiocyanatonickel(II)], [Ni2(L)2(NCS)2], 1, bis{μ‐2‐methoxy‐6‐[8‐(pyridin‐2‐yl)‐3,6‐dioxa‐2,7‐diazaocta‐1,7‐dien‐1‐yl]phenolato}bis[azidonickel(II)], [Ni2(L)2(N3)2], 2, and catena‐poly[[{2‐methoxy‐6‐[8‐(pyridin‐2‐yl)‐3,6‐dioxa‐2,7‐diazaocta‐1,7‐dien‐1‐yl]phenolato}nickel(II)]‐μ‐dicyanamidato], [Ni(L)(dca)]n, 3 {dca is dicyanamide, C2N3, and HL is 2‐methoxy‐6‐[8‐(pyridin‐2‐yl)‐3,6‐dioxa‐2,7‐diazaocta‐1,7‐dien‐1‐yl]phenol, C16H17N3O4}, with a half‐salamo‐based pyridine‐containing HL ligand have been synthesized and characterized by FT–IR, UV–Vis absorption spectroscopy, X‐ray crystallography, Hirshfeld surface analysis and density functional theory (DFT) calculations. The central NiII ions in complexes 1–3 are hosted in the half‐salamo‐based N3O‐donor cavity of the organic ligand. Complex 1 is a centrosymmetric dimer and two [Ni(L)(NCS)] units form a centrosymmetric dimeric structure, which is bridged by two phenolate O atoms. The two N atoms at the axial ends are provided by two NCS− ligands. In complex 1, each NiII ion has a six‐coordinated octahedral geometry. Complex 2 is similar to 1, but they differ in that the auxiliary NCS− ligand is replaced by N3−. However, complex 3 is a one‐dimensional coordination polymer constructed from [Ni(L)(dca)] units, which are connected by the auxiliary bidentate dca ligand viaN‐donor atoms. As with complexes 1 and 2, the NiII ion in 3 has a six‐coordinated octahedral geometry. [ABSTRACT FROM AUTHOR]

Three multinuclear Cu (II), Zn (II) and Cd (II) complexes, [Cu2(L)(μ‐OAc)]·CHCl2 (1), [Zn2(L)(μ‐OAc)(H2O)]·3CHCl3 (2) and [{Cd2(L)(OAc)(CH3CH2OH)}2]·2CH3CH2OH (3) with a single‐armed salamo‐like dioxime ligand H3L have been synthesized, and characterized by FT‐IR, UV–vis, X‐ray crystallography and Hirshfeld surfaces analyses. The ligand H3L has a linear structure and C‐H···π interactions between the two molecules. The complex 1 is a dinuclear Cu (II) complex, Cu1 and Cu2 are all five‐coordinate possessing distorted square pyramidal geometries. The complex 2 also forms a dinuclear Zn (II) structure, and Zn1 and Zn2 are all five‐coordinate bearing distorted trigonal bipyramidal geometries. The complex 3 is a symmetrical tetranuclear Cd (II) complex, and Cd1 is a hexa‐coordinate having octahedral configuration and Cd2 is hepta‐coordinate with a pentagonal bipyramidal geometry, and it has π···π interactions inside the molecule. In addition, fluorescence properties of the ligand and its complexes 1–3 have also been discussed. [ABSTRACT FROM AUTHOR]

Three newly designed containing‐PMBP N2O2‐donors complexes, [Co(L1)(CH3OH)2] (1), [{Zn(L2)(CH3OH)(H2O)}3] (2) and [Cu4(L2)4]⋅2CHCl3 (3), have been synthesized and structurally characterized using elemental analyses, infrared and UV–visible spectroscopies and single‐crystal X‐ray diffraction. X‐ray crystal structure determinations revealed that 1 consists of one Co(II) atom, one completely deprotonated (L1)2− unit and two coordinated methanol molecules. Complex 2 consists of three Zn(II) atoms, three completely deprotonated (L2)2− units, three coordinated methanol molecules and three coordinated water molecules. However, 3 includes four Cu(II) atoms, four completely deprotonated (L2)2− units and two crystallization chloroform molecules. The Co(II) and Zn(II) atoms in the structures of 1 and 2 adopt slightly distorted octahedral geometries. While, Cu(II) atoms in 3 can be best described as adopting slightly distorted square planar geometries. Complex 2 is a novel structure, and the ratio of H2L2 to Zn(II) atom is 3:3. In addition, two‐, three‐ and three‐dimensional supramolecular structures were constructed for 1, 2 and 3. Most importantly, Hirshfeld surface analysis of 1, 2 and 3 was conducted and fluorescence properties were investigated. [ABSTRACT FROM AUTHOR]

An unexpected trinuclear Co(II) complex, [Co3(L2)2(μ-OAc)2(CH3OH)2]·2CH3OH (H2L2 = 4,4′-dibromo-2,2′-[ethylenedioxybis(nitrilomethylidyne)]diphenol) constructed from a half-Salamo-based ligand (HL1 = 2-[O-(1-ethyloxyamide)]oxime-4-bromophenol) and Co(OAc)2·4H2O, has been synthesized and characterized by elemental analyses, infrared spectra (IR), UV-Vis spectra, X-ray crystallography and Hirshfeld surface analysis. The Co(II) complex contains three Co(II) atoms, two completely deprotonated (L2)2− units, two bridged acetate molecules, two coordinated methanol molecules and two crystalline methanol molecules, and finally, a three-dimensional supramolecular structure with infinite extension was formed. Interestingly, during the formation of the Co(II) complex, the ligand changed from half-Salamo-like to a symmetrical single Salamo-like ligand due to the bonding interactions of the molecules. In addition, the antimicrobial activities of HL1 and its Co(II) complex were also investigated. [ABSTRACT FROM AUTHOR]

A new homo-trinuclear Ni(II) half-salamo-based complex [Ni3(L)2(μ-OAc)2(OAc)2(CH3OH)2]·2CH3OH was synthesized via the reaction of a tridentate ligand HL (2-[O-(1-ethyloxyamide)]oxime-4-bromophenol) and Ni(OAc)2·4H2O, and characterized using elemental analyses, IR spectra, UV-Vis absorption spectra, X-ray crystallography, and Hirshfeld analysis. Interestingly, single-crystal X-ray analysis showed that the two acetate molecules were bonded simultaneously with the Ni(II) atoms by mono-dentate chelating and bidentate bridging coordination modes, respectively, and the resulting hexa-coordinate geometries were ultimately formed. Furthermore, the Hirshfeld analysis of the complex was studied. Compared with HL, the complex fluorescence intensity was significantly lowered, indicating that the Ni(II) ions have fluorescence quenching characteristics. [ABSTRACT FROM AUTHOR]

• A salamo‐like oligo(N,O-donor) ligand H3L has been synthesized. • Unusual di-nuclear Mn(III) and tetra-nuclear Cd(II) complexes have been successfully self-assembled. • The hexa-coordinated Mn(III) and Cd(II) atoms in complexes 1 & 2 form slightly distorted octahedral geometries. • Theoretical calculations and fluorescence properties of H3L and complexes 1 and 2 were also investigated. The self-assembled di-nuclear Mn(III) & tetra-nuclear Cd(II) salamo-like oligo(N,O-donor) complexes, [Mn 2 (L) 2 (CH 3 OH) 2 ]·4CH 3 OH (1) and [Cd 4 (L) 2 (η -OAc) 2 (CH 3 OH) 2 ] (2) have been constructed successfully applying the measure of solvent evaporation and characterized structurally by X-ray diffraction analyses of single crystal, IR & UV visible analyses. The single crystals of the salamo-like oligo(N,O-donor) compound H 3 L have been obtained by wet-chemical technique, its established structure is H 3 L∙CH 3 OH. The structure of complex 1 is centrally symmetrical, and both Mn(III) atoms are hexa-coordination and have slightly distorted octahedral geometries. There are two sets of intermolecular H-bonding interactions which are connected with adjacent units of the Mn(III) complexes and form a two-dimensional network structure. For the complex 2 , all of the Cd(II) atoms are also hexa-coordination and possess slightly twisted octahedral configurations. And five groups of intermolecular H-bonding interactions form a honeycomb shaped three-dimensional supramolecular structure. Additionally, the intermolecular interactions of H 3 L, complexes 1 and 2 have been quantified by Hirshfeld surface analysis for further study. Fluorescence emission spectra of H 3 L, complexes 1 and 2 were also investigated. [Display omitted] [ABSTRACT FROM AUTHOR]

• Synthesis of a uncommon chloride-bridged salamo-type Ni(II) complex. • The TD-DFT calculation verifies the type of ultraviolet electronic transition. • Quantitative analyzes of intermolecular interactions in the crystalline structures were performed by Hirshfeld analysis. • The reaction sites were predicted by IRI, ESP and other weak interaction force analysis. What is the shape of a more flexible salamo-type ligand? Unexpectedly single crystals of the ligand and a uncommon tetranuclear chloride-bridged complex with Ni(II) [Ni 4 (L) 2 (µ 2 Cl) 2 (µ 3 OMe) 2 (MeOH) 2 ] were acquired. Single-crystal X-ray analyzes revealed the true structure of the ligand to be a twisted rectilinear shape, with a unique structure providing a diverse coordination environment for the metal ions. The involvement of halogens in the bridging is uncommon, and Single-crystal X-ray analysis of the complex showed that each deprotonated methoxy group bridges three Ni(II) metals, and then three Ni(II) metals are bridged by two chloride ions, each chloride ion bridges two Ni(II) metals. At this point the geometries of all four Ni(II) atoms adopt 6-coordinated octahedral configurations. It was demonstrated in UV–visible titration test that the metal-to-ligand ratios in solution and the structure of the complex obtained by single-crystal X-ray analysis are consistent. The properties were predicted analytically by DFT theory calculations and the UV–vis absorption spectra obtained by TD-DFT theory calculations in general coincide with the test results. The weak interactions in the complex were analyzed by cell freedom, Hirshfed surface analysis, ESP and IRI calculations. Finally, the fluorescence properties were explored in detail. [Display omitted] [ABSTRACT FROM AUTHOR]

• A quinoline-appended acylhydrazone H 2 L was designed and prepared. • The Zn(II) acylhydrazone complex [Zn(HL) 2 ]·H 2 O was prepared and elucidated tructurally. • The ligand HL and its Zn(II) complex showed unique luminescent mechanochromism. • The self-assembly process and weak intermolecular forces of complexes were explained. In the work, a quinoline-appended acylhydrazone H 2 L was designed and prepared via a Schiff base condensation reaction of quinoline-2-formaldehyde and salicylhydrazide. Further, a new zinc(II) complex, [Zn(HL) 2 ]·H 2 O was synthesized by the reacting of the ligand H 2 L and Zn(NO 3) 2 ·6H 2 O in dichloromethane/ethanol solution. The ligand and its Zn(II) complex were elucidated via UV–Vis, FT-IR, DFT calculation, Hirshfeld surfaces, MEP & IRI analyses, and X-ray single-crystal diffractions. The results of Hershfield surface analysis showed that there are obvious hydrogen bond interactions and C H···π mutual effect in the Zn(II) complex. In addition, solid-state photoluminescence properties indicated that H 2 L and its Zn(II) complex represent uncommon luminescent mechanochromism tuned via intermolecular hydrogen bonds. A quinoline-appended acylhydrazone ligand H 2 L and its Zn(II) complex [Zn(HL) 2 ]·H 2 O, were prepared and elucidated structurally. The results of Hershfield surface analysis showed that there are obvious hydrogen bond interactions and C H···π mutual effect in the Zn(II) complex. In addition, solid-state photoluminescence properties indicated that H 2 L and its Zn(II) complex represent uncommon luminescent mechanochromism tuned via intermolecular hydrogen bonds. [Display omitted] [ABSTRACT FROM AUTHOR]

• The quinoline-decorated N 3 O-donor half-salamo type ligand HL was designed and synthesized. • Two novel Co(Ⅱ) complexes [Co(L)Cl] (1) and [Co(L)(NCS)] (2) were obtained by the reaction of HL with different Co(Ⅱ) salts. • Quantitative analyses of intermolecular interactions in the crystalline structures were performed by Hirshfeld surfaces analysis. Self-assembly through a quinoline-decorated N 3 O donor half-salamo-type tetradentate ligand HL and coordinative preference of Co(II) ion, two novel Co(II) complexes [Co(L)Cl] (1) and [Co(L)(NCS)] (2) were synthesized and characterized. X-ray crystallography revealed that both complexes 1 and 2 have similar mononuclear structure, in which the five-coordinated Co(II) atoms are not only surrounded by the N 3 O cavity of the deprotonated ligand (L)− unit, but also coordinated with different Cl− and NCS− anions. For the involvement of different anions, the crystal structures of the two complexes exhibit intermolecular C H···Cl and C H···S hydrogen interactions in building supramolecular assemblies, respectively. The two complexes are stabilized by C H···O, C H···N, C H···C, C H···S bonds and C H···π, π···π interactions. The spectral properties of the complexes were investigated through UV–Vis and fluorescence spectroscopy. In addition, the detailed analyses of Hirshfeld surfaces and fingerprint plots provide the basis of the intermolecular interactions in building crystal blocks. Two novel Co(II) complexes, [Co(L)Cl] (1) and [Co(L)(NCS)] (2) with a quinoline-decorated half-salamo type ligand HL were synthesized and characterized structurally. In addition, spectroscopic properties, DFT calculations and Hirshfeld surfaces analyses of HL and its two Co(II) complexes were investigated in detail. [Display omitted] [ABSTRACT FROM AUTHOR]

One mononuclear Ni(II) complex [Ni(L1)(MeOH) 2 ]·MeOH(1) and two novel trinuclear Ni(II) complexes [Ni 3 (L2) 3 (EtOH) 6 ] (2) and [Ni 3 (L2) 3 (H 2 O) 6 ] (3) constructed from N 2 O 2 -donors chelating ligands (H 2 L1 and H 2 L2) were synthesized and characterized structurally. In addition, Hirshfeld surface analyses and the fluorescence titration experiments were investigated. One mononuclear Ni(II) complex [Ni(L1)(MeOH) 2 ]·MeOH (1) and two novel trinuclear Ni(II) complexes [Ni 3 (L2) 3 (EtOH) 6 ] (2) and [Ni 3 (L2) 3 (H 2 O) 6 ] (3) constructed from symmetric N 2 O 2 -donors chelating ligands (H 2 L1 and H 2 L2) were synthesized and characterized by elemental analyses, FT-IR, UV–Vis spectra and fluorescence spectra. The structures of all three complexes were confirmed by single crystal X-ray diffraction analyses. Complex 1 includes one Ni(II) atom, one completely deprotonated (L1)2− unit and two coordinated methanol molecules, and forms an infinite 2D supramolecular network via the intermolecular hydrogen bonds. While complex 2 or 3 is trinuclear with three Ni(II) atoms, three completely deprotonated (L2)2− units and six coordinated ethanol or H 2 O molecules. These self-assembling complexes form different dimensional supramolecular structures through inter- and intramolecular hydrogen bonds. Hirshfeld surface analyses for complexes 1 , 2 and 3 were mapped with various functions and further quantification of intermolecular interactions was made through the generation of 2D fingerprint plots. In addition, the fluorescence titration experiments were used to characterize fluorescence properties of complexes 1 and 2. [ABSTRACT FROM AUTHOR]

Graphical abstract Homo-trinuclear [Zn 3 (L)(μ 2 -OAc) 2 (H 2 O)] . CH 2 Cl 2 (1) and hetero-pentanuclear [Zn 4 (L) 2 Eu(NO 3) 3 (H 2 O)] (2) and [Zn 4 (L) 2 Nd(NO 3) 3 (H 2 O)]·CH 3 CH 2 OH (3) complexes containing a coumarin-skeleton bis(salamo)-like ligand H 4 L, were successfully prepared and structurally characterized. Hirshfeld surfaces analysis and luminescences were investigated in detail. Highlights • Trinuclear ZnII (1) and pentanuclear ZnII-LnIII (Ln = Eu (2) and Nd (3)) complexes were synthesized. • The structures of complexes 1 – 3 are reported. • Hirshfeld surface and luminescences of complexes 1 – 3 were investigated. Abstract Homo-trinuclear [Zn 3 (L)(μ 2 -OAc) 2 (H 2 O)] . CH 2 Cl 2 (1) and hetero-pentanuclear [Zn 4 (L) 2 Eu(NO 3) 3 (H 2 O)] (2) and [Zn 4 (L) 2 Nd(NO 3) 3 (H 2 O)]·CH 3 CH 2 OH (3) complexes containing a coumarin-skeleton bis(salamo) ligand H 4 L, were successfully prepared and characterized via the means of elemental analyses, single crystal X-ray crystallography, FT-IR, UV–Vis absorption spectroscopy and Hirshfeld surfaces analyses. Complex 1 is a 1:3 ((L)4−:ZnII) structure, and complexes 2 and 3 are 2:4:1 ((L)4−:ZnII:LnIII) structure. All ZnII atoms in complexes 1 – 3 occupied the N 2 O 2 sites are five-coordinated with geometries of slightly distorted tetragonal pyramid and trigonal bipyramid. Rare earth metal (EuIII and NdIII) atoms are both coordinated with phenolic oxygen atoms, and eight-coordinated with the square antiprism geometries in complexes 2 and 3. Water molecules as coordinating solvents participate in the coordination. Supra-molecular structures are built by C H ... π and hydrogen bonding interactions in complexes 1 – 3. Moreover, Hirshfeld surfaces analyses of complexes 1 – 3 were also analysed in detail. Most important of all, luminescences of complexes 1 – 3 were discussed. [ABSTRACT FROM AUTHOR]

Graphical abstract The self-assembling of di-, tri- and tetra-nuclear metal(II) complexes shows propeller, butterfly and windmill type motifs, respectively. In complexes 1 and 2 , the ideal size, shape as well as strong coordination ability of OAc− as an anion significantly stabilize the aesthetic structure, while in complex 3 , the hydroxyl radical of an unexpected ligand H 2 L′, which derived from the cleavage of HL are coordinated with three Co(II) atoms at the same time. Meanwhile, complexes 1 , 2 and 3 possess a self-assembling 2D, 3D and 0D supramolecular structures by abundant noncovalent interactions. Besides, magnetic properties and Hirshfeld surface analyses were discussed. Abstract Two newly di- and tri-nuclear Cu(II) and Ni(II) complexes constructed from a half-salamo chelating ligand (HL: 2-[ O -(1-ethyloxyamide)]oxime-6-methoxyphenol), [Cu 2 (L) 2 (μ-OAc) 2 ] (1) and [{Ni 3 (μ-OAc) 2 (L) 2 (OAc) 2 ]·CHCl 3 (2), and one tetranuclear Co(II) complex [Co 4 (L′) 4 (MeOH) 4 ] (3) based on an unexpected ligand H 2 L′ derived from the cleavage of HL have been synthesized and characterized by elemental analyses, IR, UV–vis spectra, and single crystal X-ray diffraction analyses. The single crystals of complexes 1 , 2 and 3 in the process of synthesis are obtained through different routes. The complex 1 includes two Cu(II) atoms, two completely deprotonated (L)− units and two μ-acetate ions, which displays a propeller-type motif. The complex 2 contains three Ni(II) atoms, two completely deprotonated (L)− units, two μ-acetate ions, two chelating acetate ions and one crystallizing chloroform molecule, the crystal structure of complex 2 reveals a butterfly-type motif. The complex 3 is made up of four Co(II) atoms, four completely deprotonated (L′)2− units (HL′: 2-[ O -(1-hydroxyethyl)]oxime-6-methoxyphenol) and four coordinated methanol molecules, which shows a windmill-type motif. Besides, magnetic properties and Hirshfeld surface analyses were discussed. [ABSTRACT FROM AUTHOR]

• Heterobimetalic [Cu(II)2Ln(III)] (Ln = La and Ce) complexes were synthesized and characterized structurally. • It can be seen from complex 2 that the coordination ability of nitrate is stronger than that of acetic acid. • Hirshfeld surface analyses, DFT calculations and luminescences of the complexes 1 and 2 were investigated. Two heterobimetallic [Cu(II) 2 Ln(III)] (Ln = La and Ce) complexes composed of flexible bis(salamo)‐type ligand H 4 L with Cu(II) and Ln(III) atoms, [Cu 2 La(L)(ƞ 2-NO 3) 3 ]·EtOH (1) and [Cu 2 Ce(L)(ƞ 2-NO 3) 3 ]·EtOH (2) have been successfully synthesized, and characterized by IR spectra, elemental analyses, UV–Vis spectroscopy, the crystal structures of the complexes 1 and 2 were determined by single-crystal X-ray diffraction analyses. Each Cu(II) atom of the complexes 1 and 2 is located in the N 2 O 2 -donor of the completely deprotonated (L)4− unit, so that the two Cu(II) atoms have tetra-coordinated slightly distorted square planar geometries, while the Ln(III) (La or Ce) atom is located in the O 5 cavity of the ligand (L)4− unit. At the same time, there are six oxygen atoms from three bidentate nitrate groups coordinated with the Ln(III) (La or Ce) atom, resulting in the formation of an eleven-coordinated augmented sphenocorona J87. In addition, DFT calculations and Hirshfeld surfaces analyses are performed and fluorescence properties are evaluated. [Display omitted] Two heterobimetalic [Cu(II)2Ln(III)] (Ln = La and Ce) complexes composed of a flexible bis(salamo)‐type ligand H4L with Cu(II) and lanthanide(III) atoms, [Cu 2 La(L)(ƞ2-NO 3) 3 ]·EtOH (1) and [Cu 2 Ce(L)(ƞ2-NO 3) 3 ]·EtOH (2) have been successfully synthesized. The central lanthanide(III) atom forms eleven-coordinated augmented sphenocorona J87. At the same time, DFT calculations are performed and fluorescence properties are evaluated. [ABSTRACT FROM AUTHOR]

Two novel complexes [Cu(L)(OAc)]·CH 3 OH (1) and [Ni(L)(OAc)] (2) formed with a quinolone-modified half-salamo-like ligand (HL) were successfully synthesized and characterized structurally. In addition, Fluorescence properties, DFT theoretical calculations and Hirshfeld surfaces analyses of the ligand HL and its corresponding complexes were also investigated. [Display omitted] • The introduction of quinoline into half-salamo-like ligand HL has been developed triumphantly. • Two novel complexes [Cu(L)(OAc)]·CH 3 OH (1) and [Ni(L)(OAc)] (2) were synthesized and ascertained structurally. • Fluorescence properties, DFT theoretical calculation and Hirshfeld surfaces analyses were investigated. Two novel Cu(II) and Ni(II) complexes, [Cu(L)(OAc)]·CH 3 OH (1) and [Ni(L)(OAc)] (2) formed with a newly designed quinolone-modified half-salamo-like ligand (HL) were successfully obtained. Elemental analyses, infrared spectra and UV–visible absorption spectra were employed triumphantly to characterize the complexes 1 and 2. X-ray single-crystal diffraction analysis results indicated that the complex 1 is composed of a fully deprotonated ligand (L)- unit, one Cu(II) atom and one monodentate coordinated acetate ion. For the complex 1 , the central Cu(II) atom is five coordinated adopting a slightly distorted triangular biconical geometry, while the complex 2 has two independent structural units (molecules A and B), which shows chemically identical but crystallographically independent. The central Ni(II) atom is six coordinated possessing a distorted octahedral configuration. In addition, Fluorescence properties, DFT theoretical calculations and Hirshfeld surfaces analyses of the ligand HL and its corresponding complexes 1 and 2 were also investigated in detail. [ABSTRACT FROM AUTHOR]

• The pyridine-including half-salamo-like ligands HL1 and HL2 have been developed successfully. • Two first Co(III) complexes, [Co(L1)(N 3) 2 ] (1), and [Co(L2)(N 3) 2 ] (2) were synthesized and ascertained structurally. • The complexes 1 and 2 are unusual salamo-like Co(III) complexes with variable valence. This situation has never reported in the previous salamo-based complexes. Two structurally novel Co(III) complexes have been successfully constructed from the pyridine-including half-salamo-like ligands (HL1 and HL2), namely as [Co(L1)(N 3) 2 ] (1) and [Co(L2)(N 3) 2 ] (2). The structural features of complexes 1 and 2 have been confirmed by means of single crystal X-ray diffraction experiment. The structural studies revealed that complexes 1 and 2 have similar structures. The characterization of the two ligands and their Co(III) complexes was ascertained by means of infrared spectra, ultraviolet spectra and Hirshfeld surfaces analyses. In addition, compared with the ligands HL1 and HL2, the fluorescence intensities of the corresponding complexes 1 and 2 decreased significantly. When Co(II) salt was gradually added to the ligand solution, the intensity of the fluorescence emission peak decreased with the continuous addition of Co(II) salt until this trend stopped, which indicates that the introduction of Co(II) ion leads to the charge transfer from the ligand to Co(III) ion. Two structurally novel Co(III) complexes have been successfully constructed from the pyridine-including half-salamo-like ligands (HL1 and HL2), namely as [Co(L1)(N 3) 2 ] (1) and [Co(L2)(N 3) 2 ] (2). The characterization of the two ligands and their Co(III) complexes was ascertained by means of infrared spectra, ultraviolet spectra, X-ray crystallography, fluorescence spectra and Hirshfeld surfaces analyses. [Display omitted] [ABSTRACT FROM AUTHOR]

• A new kind of single‐armed salamo‐type ligand H 3 L and two corresponding Zn(II) complexes have been synthesized. • All of the Zn(Ⅱ) atoms in complexes 1 and 2 are penta-coordinated, highly distinct configurations are obtained because of the introduction of two kinds of counter-anions. • Fluorescence properties of H 3 L and complexes 1 and 2 were also investigated. Di- and tetra-nuclear Zn(II) complexes, [Zn 2 (L)(µ -OAc)(CH 3 OH)]·CH 3 OH (1) and [Zn 4 (L) 2 (OMe) 2 ]·2CH 3 COCH 3 ·CH 3 OH (2) have been successfully self-assembled by the reaction of a single‐armed salamo‐type ligand (H 3 L), Zn(OAc) 2 ·2H 2 O and Zn(NO 3) 2 ·6H 2 O, respectively. In the ligand H 3 L, tetradentate N 2 O 2 donor part of pocket I and NO 2 donor part of pocket II are designed to bond Zn(II) atoms, then unusually structural complexes were obtained by counteranion-driven self-assembled. Both complexes 1 and 2 are characterized by elemental analyses, IR spectra, UV-Vis spectra and single crystal X-ray diffraction. All of the Zn(II) atoms in complexes 1 and 2 are penta-coordinated, but highly distinct configurations are obtained because of the introduction of two kinds of counter-anions. In complex 1 , μ- OAc− counter-anion connects the two Zn(II) atoms in one ligand. In complex 2 , μ- OMe− counter-anions link the Zn(II) atoms within two ligand molecules and the structure of complex 2 is more complicated. What's more, in complex 1 , all Zn(II) atoms have the geometries of distorted trigonal bipyramid, while in complex 2 , all Zn(II) atoms have the geometries of distorted square pyramid. There are obvious π···π stacking interactions existing in complexes 1 and 2 , which are quantitatively valued by Hirshfeld surfaces analyses. Fluorescence properties are also investigated. Di- and tetra-nuclear Zn(II) complexes, [Zn 2 (L)(µ -OAc)(CH 3 OH)]·CH 3 OH (1) and [Zn 4 (L) 2 (OMe) 2 ]·2CH 3 COCH 3 ·CH 3 OH (2) have been successfully synthesized and structurally characterized. The fluorescence properties were also investigated. [Display omitted] [ABSTRACT FROM AUTHOR]

Three novel N 4 -cavity Cu(II), Ni(II) and Zn(II) complexes were successfully synthesized via the reactions of a novel pyridine-containing N 4 -cavity bisoxime ligand L. All three complexes are monoclinic systems. Complexes 2 and 3 form centrosymmetric helical molecules. Complexes 1 – 3 have been characterized by elemental analysis, IR, UV–Vis spectroscopy and single crystal X-ray crystallography. In addition, supramolecular interactions, Hirshfeld surface analysis to analyze the crystal properties have been studied. [Display omitted] • A novel ligand L with N4 cavity was synthesized and characterized. • Three excess metal single crystals were synthesized via the ligand L. • Hirshfeld surface analysis was performed on single crystals. Three novel N 4 -cavity Cu(II), Ni(II) and Zn(II) mononuclear complexes, [Cu(L)(NO 3) 2 ][Cu(L)(NO 3)]NO 3 (1) [Ni(L)(NO 3) 2 ] (2) and [Zn(L)(NO 3) 2 ] (3) were successfully synthesized via the reactions of a pyridine-containing N 4 -cavity bisoxime ligand L (L = 2,2′-[Ethylenedioxobis(azetidinyl)]pyridine) with Cu(II), Ni(II) and Zn(II) nitrates, respectively. Complexes 1 – 3 were characterized via elemental analysis, IR, UV–Vis spectra and X-ray crystallography. All three complexes are monoclinic systems, containing one M(II) atom and one (L) ligand moiety. Complexes 2 and 3 form centrosymmetric molecules. In addition, supramolecular interactions, Hirshfeld surface analysis were used to analyze the crystal properties that have been studied. [ABSTRACT FROM AUTHOR]

Three trinuclear complexes 1 - 3 possessed inversion centers have been successfully synthesized by wet-chemical method using asymmetric salamo-based polydentate chelating ligand (H 2 L) with Co(OAc) 2 ·4H 2 O and Ni(OAc) 2 ·4H 2 O, respectively. [Display omitted] Three trinuclear complexes, [{CoL(MeOH)(μ -OAc)} 2 Co] (1), [{CoL(EtOH)(μ -OAc)} 2 Co]·2CH 3 CH 2 OH (2) and [{NiL(MeOH)(μ -OAc)} 2 Ni]·2CH 3 OH (3) have been successfully synthesized by wet-chemical method using asymmetric salamo-based polydentate chelating ligand (H 2 L) with transition metal(II) acetate (Co(OAc) 2 ·4H 2 O or Ni(OAc) 2 ·4H 2 O). The ligand H 2 L with N 2 O 2 coordination cavity can accommodate transition metals, at the same time, the oxygen atoms of the phenolic hydroxyl groups can bridge the metal atoms to obtain muiltnuclear metal complexes. There are inversion centers in complexes 1 – 3 and all M(II) atoms possess six-coordinated distorted octahedral geometries. Complexes 1 and 3 are further assembled into extended two-dimensional supramolecular via intermolecular interactions, but complex 2 forms three-dimensional supramolecular structure. The interactions were quantitatively determined by Hirshfeld surfaces analyses. Significantly, complexes 1 – 3 have been characterized by elemental analyses, IR spectra, UV–Vis spectroscopy and X-ray crystallography analyses. Fluorescence properties were also investigated. [ABSTRACT FROM AUTHOR]

Penta-coodinated homo-binuclear [Cu 2 (L)(CH 3 OH)]ClO 4 ·CH 3 OH (1) , [Cu 2 (L)(CH 3 CH 2 OH)]ClO 4 (2) and homo-tetranuclear [{Cu 2 (HL)Cl(μ -Cl)} 2 2CHCl 3 (3) complexes containing a symmetrical multi-halogen-substituted bis(salamo)-based ligand H 3 L have been successfully synthesized and characterized by elemental analyses, FT-IR and UV–Vis absorption spectroscopy, fluorescence spectra, Hirshfeld surfaces analyses and density functional theory (DFT) calculations. [Display omitted] • Di- and tetranuclear complexes 1 , 2 and 3 were synthesized and characterized structurally. • The complex 3 possesses a novel tetranuclear structure in which the two [Cu 2 (HL)Cl] units are bridged by two chloride anions. • Hirshfeld surfaces, DFT calculation and luminescences of three Cu(II) complexes were investigated. Penta-coordinated homo-binuclear [Cu 2 (L)(CH 3 OH)]ClO 4 ·CH 3 OH (1) , [Cu 2 (L)(CH 3 CH 2 OH)]ClO 4 (2) and homo-tetranuclear [{Cu 2 (HL)Cl(μ -Cl)} 2 ·2CHCl 3 (3) complexes containing a symmetrical multi-halogen-substituted bis(salamo)-based ligand H 3 L have been successfully synthesized and characterized by elemental analyses, FT-IR and UV–Vis absorption spectroscopy, Hirshfeld surfaces analyses and density functional theory (DFT) calculations. The crystal structures of the three Cu(II) complexes were determined by single crystal X-ray crystallography. All the Cu(II) atoms in the binuclear complexes 1 and 2 are located in the N 2 O 2 cavities of the fully deprotonated (L)3- unit, and penta-coordinated with slightly distorted square pyramidal geometries. Methanol and ethanol molecules are coordinated to the Cu(II) atoms in the complexes 1 and 2 , respectively. Most surprisingly, the complex 3 has a novel penta-coordinated tetranuclear structure unreported earlier. The four Cu(II) atoms in the complex 3 are all penta-coordinated, and the geometries around the Cu(II) centers in complexes 3 are square pyramid. It is worth noting that two binuclear [Cu 2 (HL)Cl] units are connected to two bridged chloride ions and the complex 3 has a crystallographically imposed inversion center at the midpoint of Cu2 and Cu2#1. The supramolecular structures of the complexes 1 , 2 and 3 are formed by inter-molecular interactions. In addition, Hirshfeld surfaces analyses showed short-range interactions on the molecular surfaces of the complexes 1 , 2 and 3. Furthermore, the fluorescence properties of H 3 L and its three Cu(II) complexes are also discussed. [ABSTRACT FROM AUTHOR]

• Two multi-nuclear Ni(II)-based complexes have been successfully prepared by the complexation of more flexible salamo-type ligand (H 2 L) with nickel salts of different anions. • The structure of tetra-nuclear complex 2 is particularly unique because the flexibility of the ligand is better, which creates conditions for the intramolecular self-assembly. Two new tri- and tetra-nuclear Ni(II)-based complexes, [{NiL(EtOH)(μ -OAc)} 2 Ni]·4EtOH (1) and [Ni 4 L 2 (μ 3 -OMe) 4 (MeOH) 4 ] (2), supported by a more flexible salamo-type ligand H 2 L containing coumarin functional groups have been synthesized. Complex 1 is tri-nuclear, including three Ni(II) atoms with hexa-coordinated octahedral geometries. X-ray single-crystal structure analysis revealed that complex 2 is a novel tetra-nuclear structure previously unreported, and the geometry of four Ni(II) atoms with hexa-coordinate can be regarded as octahedron. Interestingly, due to the improvement of the flexibility of salamo-type ligand H 2 L, complex 2 is obtained by the form of intramolecular self-assembly. Moreover, the fluorescence properties of H 2 L and its Ni(II)-based complexes were studied. Subsequently, the supramolecular structure, Hirshfeld surfaces analyses and DFT calculations of the two Ni(II)-based complexes have been performed. Image, graphical abstract Two new tri- and tetra-nuclear Ni(II)-based complexes, [{NiL(EtOH)(μ -OAc)} 2 Ni]·4EtOH (1) and [Ni 4 L 2 (μ 3 -OMe) 4 (MeOH) 4 ] (2) , supported by a more flexible salamo-type ligand H 2 L containing coumarin functional groups have been synthesized and characterized structurally. Interestingly, complex 2 is a novel tetra-nuclear structure previously unreported. The fluorescence properties, Hirshfeld surfaces analyses and DFT calculations of H 2 L and its Ni(II)-based complexes were studied. [ABSTRACT FROM AUTHOR]

Three new multi-nuclear Cu(II) complexes have been successfully synthesized by the one-pot reaction of a bis(salamo)-based ligand H 3 L and different copper(II) salts and characterized structurally. • Three new multi-nuclear Cu(II) complexes have been successfully synthesized and characterized structurally. • Complex 3 is a novel penta-nuclear structure derived of the ligand (HL)2- units. • Effects of counteranions and fluorescence properties were also investigated. Three new multi-nuclear Cu(II) complexes, [Cu 4 (L) 2 (CH 3 OH) 2 ](NO 3) 2 ·2CH 3 OH (1), [Cu 4 (L) 2 (CH 3 OH)(CH 3 CN)](ClO 4) 2 ·2CH 3 OH (2) and [Cu 4 (HL) 2 (μ 2 -Cl) 2 Cl 2 (CH 3 CH 2 OH) 2 ][CuCl 2 ]·CHCl 3 (3) have been successfully synthesized by the one-pot reaction of a bis(salamo)-based ligand H 3 L with Cu(NO 3) 2 ·3H 2 O, Cu(ClO 4) 2 ·6H 2 O and CuCl 2 ·2H 2 O, respectively. Complexes 1 and 2 are monoclinic systems including four Cu(II) atoms with two completely deprotonated ligand (L)3- units, which form centrosymmetric helical molecules. Complex 3 is triclinic system including five Cu(II) atoms with two incompletely deprotonated ligand (HL)2- units, which forms an expanded structural molecule. Complexes 1 – 3 have been characterized by elemental analyses, IR, UV–Vis spectroscopy and single crystal X-ray crystallography. In addition, supramolecular interactions, Hirshfeld surfaces analyses, effects of counteranions and fluorescence properties were also investigated. [ABSTRACT FROM AUTHOR]

Three new complexes 1 – 3 coordinated to a more flexible salamo-based ligand have been successfully prepared and characterized structurally. The structure of the complex 3 is novel, and self-assemblied by a more flexible salamo-based ligand. • Three complexes have been successfully prepared. • These complexes have been characterized structurally. • Due to the flexibility of ligands, the structure of complex 3 is more unique. Three new multinuclear complexes, [{CoL(MeOH)(μ -OAc)} 2 Co]·6CH 3 OH (1) [{NiL(H 2 O)(μ -OAc)} 2 Ni]·6CH 3 OH·0.442H 2 O (2) and [{Zn 2 L 2 (μ -OH)} 2 ]·2NH(CH 2 CH 3) 3 ·4CH 3 OH·H 2 O (3) , based on a more flexible salamo-based ligand H 2 L containing coumarin functional groups have been synthesized and characterized structurally. The complex 1 is trinuclear, and all Co(II) atoms have octahedral geometries. A similar trinuclear complex 2 involving three Ni(II) atoms with hexa -coordinated octahedral geometries was obtained. For the complex 3 , it is a novel symmetric tetranuclear structure, and four Zn(II) atoms have penta -coordinated trigonal bipyramidal geometries. It is worth noting that the intramolecular self-assembly is achieved by changing the flexibility of salamo-based ligand in the complex 3. In addition, fluorescence titration experiments of the three complexes were carried out. The supramolecular structures of the three complexes were constructed via intermolecular hydrogen bond or π-π stacking interactions, and Hirshfeld surfaces analyses and DFT calculations were performed on the three complexes. [ABSTRACT FROM AUTHOR]

Two newly designed tetranuclear metal(II) complexes, [{Co(L)(μ -OAc)Co(CH 3 OH) 2 } 2 and [{Ni(L)(DMF)(μ -OAc)Ni} 2 derived from an unsymmetrical salamo-like ligand (H 3 L: 6-hydroxy-6′-methoxy-2, 2′-[ethylenediyldioxybis(nitrilomethylidyne)]diphenol) were synthesized and characterized by elemental analyses, infrared spectroscopy, ultraviolet–visible absorption spectroscopy, fluorescence spectroscopy, X-ray single crystal diffraction and Hirshfeld surfaces analyses. • Tetranuclear Co(II) and Ni(II) complexes were synthesized and characterized structurally. • The crystal structures of Co(II) and Ni(II) complexes are very interesting. • Hirshfeld surfaces and fluorescent properties of the Co(II) and Ni(II) complexes were investigated. Two newly designed tetranuclear transition metal(II) complexes, [{Co(L)(μ -OAc)Co(CH 3 OH) 2 } 2 and [{Ni(L)(DMF)(μ -OAc)Ni} 2 derived from an unsymmetrical salamo-like donor-N 2 O 4 ligand (H 3 L: 6-hydroxy-6′-methoxy-2, 2′-[ethylenediyldioxybis(nitrilomethylidyne)]diphenol) were synthesized and characterized by elemental analysis, FT-IR, UV-vis, fluorescence spectroscopy, X-ray crystallography and Hirshfeld surface analysis. The Co(II) complex includes two fully deprotonated (L)3− moieties, two μ-acetato ligands and four coordinated methanol molecules, bearing a highly symmetrical tetranuclear structure. The terminal Co(II) ions are penta-coordinated and have slightly twisted triangular bipyramidal geometries, and the central Co(II) ions are hexa-coordinated and possess slightly twisted octahedral geometries. The Co(II) complex was self-assembled by adequate intermolecular hydrogen bonding interactions giving rise to an infinite two-dimensional supramolecular structure. The Ni(II) complex adopts a symmetric tetranuclear structure including two fully deprotonated (L)3− units, two coordinated DMF molecules, and two μ-acetato ligands. All the Ni(II) ions are hexa-coordinated and have slightly twisted octahedral geometries. At the same time, the fluorescent properties and Hirshfeld surfaces analyses of the Co(II) and Ni(II) complexes were also investigated in detail. [ABSTRACT FROM AUTHOR]