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Samples of (110), (100), and (111) MgO single crystals were implanted with 70 keV N ions at room temperature. All as-implanted samples showed room temperature hysteresis in magnetization loops. The observed saturation magnetization (Ms) was 0.79 × 10−4 emu/g, 1.28 × 10−4 emu/g, and 1.5 × 10−4 emu/g for (110), (100) and (111) orientation implanted-MgO and follows the relation Ms(111) > Ms(100) > Ms(110), indicative of crystalline orientation-dependent ferromagnetism in N-implanted MgO. The samples were characterized by X-ray photoelectron spectroscopy (XPS), high resolution X-ray diffraction (HRXRD), reciprocal space mapping (RSM), and photoluminescence (PL). The results indicated that the amount of N-substitute-O and N-interstitial defects in these three N-implanted MgO samples showed the same changing tendency as compared with Ms data. Thus, we conclude that the N-substitute-O and N-interstitial defects may play a crucial role in controlling the N+-implanted-induced ferromagnetism. [ABSTRACT FROM AUTHOR]

Luminescent piezoelectric materials promise a stratagem for controlling the optical process by electric field, which would benefit for future optoelectronic devices. Here, Er3+ doped (Ba 0.85 Ca 0.15) (Zr 0.1 Ti 0.9)O 3 (BCZT: Er3+) piezoelectric ceramics are prepared to demonstrate the proof of concept. In addition to excellent intrinsic piezoelectricity and ferroelectricity, BCZT: Er3+ ceramics exhibit simultaneously strong green upconversion emissions under excitation of 980 nm. Remarkable photoluminescence (PL) quenching phenomenon as well as significant changes on relative intensities of stark lines are observed under external poling electric field. Furthermore, field dependent piezoelectric constant d 33 and photoluminescence quenching ratio show similar variation trend and finally saturate for E > 3.5 kV/mm, which provides a noncontact strategy to monitor the piezoelectric constant d 33. The PL quenching triggered by electric field in BCZT: Er3+ ceramics is ascribed to the decreased asymmetry originating from field-induced structural transformation from a significant fraction of the tetragonal phase to rhombohedral phase. Our work would be helpful for expanding the scope of luminescent piezoelectric materials and promising future optoelectronic and optical devices with cross-coupled physical properties. • Ferroelectricity and upconversion emissions coexist in BCZT: Er3+. • Electric field can modulate photoluminescence and relative intensity of stark lines. • A noncontact strategy to monitor the piezoelectric constant is proposed. • The mechanism of electric field-photoluminescence coupling is analyzed. [ABSTRACT FROM AUTHOR]

Abstract A series of orange-red emitting Sm3+ activated Ba 0.85 Ca 0.15 Ti 0.90 Zr 0.10 O 3 (BCZT: x Sm3+, x = 0.001–0.007) are synthesized by a conventional solid-state reaction method. The Sm3+ ions composition dependent photoluminescence properties are systematically investigated. Under the excitation of a 407 nm near-ultraviolet light, the ceramics exhibit strong characteristic emission of Sm3+ ions with dominant orange-red emission peak at around 595 nm, which is ascribed to the transition of 4G 5/2 → 6H 7/2. The BCZT: 0.004Sm3+ ceramic displays the optimal emission among these Sm3+-doped BCZT solid solutions. Moreover, the photoluminescence intensity exhibits extremely sensitive to temperature, suggesting that BCZT: 0.004Sm3+ could be applicable for temperature sensing. A maximum relative sensitivity of 1.89% K−1 at 453 K is obtained. Furthermore, the existence of ferroelectricity in the BCZT host combined with Sm3+ activated photoluminescence properties could be useful for developing optical-electro multifunctional materials and devices. [ABSTRACT FROM AUTHOR]

The metamagnetic transition, magnetocaloric and magnetoresistance effects are investigated in polycrystalline Sm 0.55 (Sr 0.5 Ca 0.5 ) 0.45 MnO 3 (SSCMO) manganite. A sharp magnetization jump at Curie temperature ( T C ) 73.5 K with large thermal hysteresis is observed. Magnetic measurements and Arrott plots analysis indicate that the transition is first order in nature. Under a low magnetic field change of 1 T, the magnetic entropy change exhibits a peak value of − Δ S M max ( T ) =4.01 J/kg K with relative cooling power (RCP) value of 44.1 J/kg in the vicinity of T C . The mechanism of charge conduction in insulator phase is polaron transport. Large negative magnetoresistance ratio with value of ~99% is obtained within a broad temperature range below metal insulator transition temperature under 1 T magnetic field. These results indicate the potential applications of SSCMO in magnetic refrigeration and spintronics devices. [ABSTRACT FROM AUTHOR]

• The quantum cutting was directly observed and confirmed in CGP:Tm3+. • The improved QC model was established in Tm3+ ion. • The effect of Tm3+ concentration on the spectral characteristics was clarified. • The investigations can help to understand the QC and ET processes in Tm3+. In this work, to develop new quantum cutting (QC) luminescent materials and clarify the QC process, a series of Tm3+-activated Ca 9 Gd(PO 4) 7 (CGP) phosphors were prepared by conventional high-temperature solid state reaction method. The phase purity of the samples was checked by XRD patterns, and the structural features were analyzed on the basis of Rietveld refinement. The emission spectra of Tm3+ were measured by exciting at different wavelengths, in which the QC was identified. The main QC model was proposed when the Tm3+ is excited into 1D 2 level. The occurrence of QC was further verified by comparing the decay lifetimes on 3H 4 level under 357, 470 and 685 nm excitation. With increasing Tm3+ concentration, it was found that the 3H 4 →3H 6 transition intensity around 806 nm exhibits faster increase rate than other ones by exciting at either 357 or 470 nm. This increase rate is more effective under 357 nm excitation thanks to the existence of QC process. The above investigation could show instructional significance for the development of other rare earth ions doped luminescent materials. [ABSTRACT FROM AUTHOR]

Abstract: Six new triorganotin(IV) complexes, {(R3Sn)2[C7H14(COO)2]}n (R = Me: 1), (R3Sn)2[C7H14(COO)2] (R = Bu: 2; Ph: 3), {(R3Sn)2[C11H9NO2(COO)2]} n ·Y (R = Me, Y = CH2Cl2: 4, R = Bu, Y = 0: 5) and (R3Sn)2[C11H9NO2(COO)2] (R = Ph: 6) have been prepared by treatment of 2,4-diethylglutaric acid, phthalyl-glutamic acid and the corresponding R3SnCl (R = Me, Bu, Ph) with sodium ethoxide in methanol. All the complexes were characterized by elemental analysis, FT-IR, NMR (1H, 13C, 119Sn) spectroscopy, and TGA. Except for 3 and 6, all of the complexes were also characterized by X-ray crystallography. The structural analyses reveal that complexes 1 and 4 have 2D network structures in which 2,4-diethylglutaric acid and phthalyl-glutamic acid act as tetradentate ligands coordinated to trimethyltin(IV) ions. Complex 2 has a dinuclear structure, and complex 5 has a 1D zigzag chain structure and forms a 2D supramolecular framework through intermolecular C–H⋯O interactions. [Copyright &y& Elsevier]

Abstract: Eight new organotin (IV) carboxylates, (R3Sn)4(nap)4 (R = Me 1, n-Bu 2), [(R3Sn) (nap)] n (R = Ph 3, PhCH2 4), (R2Sn) (nap)2 (R = n-Bu 5, Ph 6, PhCH2 7) and {[R2Sn(nap)]2O}2 (R = Me 8) (nap = (S)-(+)-6-methoxy-α-methyl-2-naphthaleneaceto anion) have been synthesized. All of the complexes have been characterized by elemental analysis, FT–IR, NMR (1H, 13C and 119Sn) spectra. Among these complexes, complexes 1, 3, 5 and 8 were also characterized by X-ray crystallography diffraction analysis, and the data of X-ray crystallography diffraction indicated that complexes 1, 3 and 5 are new chiral organotin (IV) carboxylates complexes. The structural analyses show that complex 1 has a tetranuclear Sn4O8 macrocycle structure, complex 3 has a 1D spring-like chiral helical chain with a columnar channel, complex 5 possesses a dimer structure, and complex 8 has a supramolecular chainlike ladder structure through weak intermolecular non-covalent O…O interactions. [Copyright &y& Elsevier]

Abstract: A series of new triorganotin(IV) pyridinecarboxylates with 6-hydroxynicotinic acid (6-OH-3-nicH), 5-hydroxynicotinic acid (5-OH-3-nicH) and 2-hydroxyisonicotinic acid (2-OH-4-isonicH) of the types: [R3Sn (6-OH-3-nic)·L] n (I) (R=Ph, L=Ph·EtOH, 1; R=Bn, L=H2O·EtOH, 2; R=Me, L=0, 3; R= n-Bu, L=0, 4), [R3Sn (5-OH-3-nic)] n (II) (R=Ph, 5; R=Bn, 6; R=Me, 7; R= n-Bu, 8), [R3Sn (2-OH-4-isonic·L)] n (III) (R=Bn, 9, L=MeOH; R=Me, L=0, 10; R=Ph, 11, L=0.5EtOH) have been synthesized. All the complexes were characterized by elemental analysis, TGA, IR and NMR (1H, 13C, 119Sn) spectroscopy analyses. Among them, except for complexes 5 and 6, all complexes were also characterized by X-ray crystallography diffraction analysis. Crystal structures show that complexes 1–10 adopt 1D infinite chain structures which are generated by the bidentate O, O or N, O and the five-coordinated tin centers. Significant O–H⋯O, and N–H⋯O intermolecular hydrogen bonds stabilize these structures. Complex 11 is a 42-membered macrocycle containing six tin atoms, and forms a 2D network by intermolecular N–H⋯O hydrogen. [Copyright &y& Elsevier]

Abstract: Eight new organostannoxane-based multiredox assemblies containing-Schiff-base-triazole ligand peripheries have been readily synthesized by hydrolysis or solvothermal synthetic routes. The reactions of the diorganotin dichloride with the Schiff-base-containing-triazole ligand afford the following types: [(Me2Sn)2O2(Ln)]2 (n =1, for 1) [(Me2Sn)2O(RO)(Ln)]2 (R=Et, n =2, for 2; R=Me, n =3, for 3), [(n-Bu2Sn)2O2(Ln)]2 (n =1, for 4; n =2, for 5; n =3, for 6) and [(Me2Sn)2Ln2O]2 ·L (n =2; L=H2O for 7, L=CH3OH for 8). All the complexes were characterized by elemental analysis, IR, 1H, 13C and 119Sn spectra analyses. Except for complexes 4 and 6, the other complexes are also characterized by X-ray crystallography diffraction analyses. Complexes 1–3 and 5 show similar structures containing a Sn4O4 ladder-shaped skeleton in which the N atom from a corresponding thione-form deprotonated Schiff base coordinated to the exo tin atoms in monodentate chelating agent. Complex 7 and 8 show a novel framework containing a Sn2O2 symmetrical core with two N atoms from triazole moiety coordinated to tin atoms. Weak but significant intermolecular hydrogen bondings, C–H⋯π stacking or non-bonded S⋯S interaction lead to aggregation and self-assembly of these complexes into 1D, 2D or 3D supramolecular frameworks. [Copyright &y& Elsevier]

Abstract: A series of triorganotin (IV) complexes with 2,3,4,5-tetrafluorobenzoic acid and mixed-ligands of the types: R3Sn(O2CC6HF4) m ·L (m =1, L=0, R=Ph 1; m =1, L=Ph3PO, R=Ph 4, Me 5), [R3Sn(O2CC6HF4)] m ·L (m =2, L=4,4′-bipy, R=Ph 2, Me 3; m = n, L=0, R=Me 6), and [R3Sn(O2CC6HF4)·(H2O)] m ·L·C2H5OH (m =2, L=Phen, R=Ph 7, Me 8), (4,4′-bipy=4,4′-bipyridyl; Phen=1,10-phenanthroline), have been synthesized by the reaction of triorganotin chloride and 2,3,4,5-tetrafluorobenzoic acid in the presence of mixed-ligands: 4,4′-bipy, triphenylphosphine oxide, or phen. All complexes were characterized by elemental analysis, IR, 1H, 13C, 119Sn NMR spectroscopy analysis. Except for 5 and 8, all the complexes were also characterized by X-ray crystallography. [Copyright &y& Elsevier]

Abstract: Eight new organoantimony(V) complexes with 1-phenyl-1H-tetrazole-5-thiol [L1H] and 2,5-dimercapto-4-phenyl-1,3,4-thiodiazole [L2H] of the type R n SbL5− n (L=L1: n =4, R= n-Bu 1, Ph 2, n =3, R=Me 3, Ph 4; L=L2: n =4, R= n-Bu 5, Ph 6, n =3, R=Me 7, Ph 8) have been synthesized. All the complexes 1–8 have been characterized by elemental, FT-IR, 1H and 13C NMR analyses. Among them complexes 2, 6 and 8 have also been confirmed by X-ray crystallography. The structure analyses show that the antimony atoms in complexes 2 and 6 display a trigonal bipyramid geometry, while it displays a distorted capped trigonal prism in complex 8 with two intramolecular Sb⋯N weak interactions. Furthermore, the supramolecular structure of 2 has been found to consist of one-dimensional linear molecular chain built up by intermolecular C–H⋯N weak hydrogen bonds, while a macrocyclic dimer has been found in complex 6 linked by intermolecular C–H⋯S weak hydrogen bonds with head-to-tail arrangement. Interestingly, one-dimensional helical chain is recognized in complex 8, which is connected by intermolecular C–H⋯S weak hydrogen bonds. [Copyright &y& Elsevier]

Abstract: A series of new triorganotin(IV) complexes with 4-hydroxy-2-mercapto-6-methylpyrimidine (L1H2), 4-hydroxy-2-mercapto-pyrimidine (L2H2), 2,4(1H,3H)-pyrimidinedithione (L3H2) () of the type R3SnLSnR3 (R=Me 1, 4, 7; R=Ph 2, 5, 8; R=PhCH2 3, 6, 9) have been synthesized by reactions of triorganotin(IV) chloride and corresponding ligands. All complexes are characterized by elemental analyses, IR spectra and NMR spectra analyses. Among them, complexes 2, 5 and 8 are also characterized by X-ray crystallography diffraction analyses. Significant π⋯π stacking, C–H⋯π interactions and intramolecular hydrogen bonds stabilize these structures. [Copyright &y& Elsevier]

Abstract: A series of new triorganotin(IV) pyridinedicarboxylates [(C2H5)3NH][(Me3Sn)3(2,6-pdc)2(H2O)2] (1), [(C2H5)3NH][(Ph3Sn)3(2,6-pdc)2(H2O)2] (2), [(C2H5)3NH]{[(PhCH2)3Sn]3(2,6-pdc)2(H2O)2} (3), [Me3Sn(3,5-pdc)] n (4), [Ph3Sn(3,5-pdc)] n (5), [(PhCH2)3Sn(3,5-pdc)] n (6), [(Me3Sn)2(2,5-pdc)] n (7), [(Ph3Sn)2(2,5-pdc)] n (8) and {[(PhCH2)3Sn]2(2,5-pdc)} n (9) were synthesized by the reaction of trimethyltin(IV), triphenyltin(IV) or tribenzyltin(IV) chloride with 2,6(3,5 or 2,5)-H2pdc (pdc=pyridinedicarboxylate) when triethylamine was added. Complexes 1–9 have been characterized by elemental, IR, 1H, 13C and 119Sn NMR analyses. Among them complexes 1, 5 and 7 have also been characterized by X-ray crystallographic diffraction analyses. Complex 1 has a trinuclear structure and forms a 2D supramolecular structure due to the coordinated water molecules via hydrogen bonds to the pendant O atoms of the carboxyl groups and the N atoms derived of the pyridine ring. Complex 5 forms a 1D polymeric chain by the intermolecular Sn⋯N (N atom derived of pyridine ring) interactions. Complex 7 has a network structure where 2,5-pyridinedicarboxylate acts as a tetradentate ligand coordinated to trimethyltin(IV) ions. [Copyright &y& Elsevier]

Abstract: The triorganotin(IV) derivatives of 2-mercapto-4-quinazolinone (HSqualone) of the type, R3SnL (R=Ph 1, CH3 2, PhCH2 3, p-F-PhCH2 4, o-F-PhCH2 5, n-Bu 6), were obtained by the reaction of the R3SnCl and HSqualone with 1:1 molar ratio in benzene. All complexes 1–6 were characterized by elemental analyses, IR, 1H and 13C NMR spectroscopy and the crystal structures of complexes 1–3 were also confirmed by X–ray crystallography. The structure analyses reveal that the tin atoms of complexes 1–3 are all distorted tetrahedral geometries. Furthermore, the dimeric structures in complexes 1–3 have also been found linked by intermolecular O–H⋯N or N–H⋯O hydrogen bonding interaction. Interestingly, the dimers of complexes 2 and 3 are further linked into one-dimensional chain through intermolecular C–H⋯S and C–H⋯O weak hydrogen bonding interactions, respectively. [Copyright &y& Elsevier]

Abstract: A series of organotin (IV) complexes with 6-amino-1,3,5-triazine-2,4-dithiol of the type [(R n SnCl4−n )2 (C3H2N4S2)] (n =3: R=Me 1, n-Bu 2, PhCH2 3, Ph 4; n =2: R=Me 5, n-Bu 6, PhCH2 7, Ph 8) have been synthesized. All the complexes 1–8 have been characterized by elemental analysis, IR, 1H and 13C NMR spectra. Among them complexes 1, 4, 5 and 8 have also been characterized by X-ray crystallography diffraction analyses, which revealed that the tin atoms of complexes 1, 4, 5 and 8 are all five-coordinated with distorted trigonal bipyramid geometries. [Copyright &y& Elsevier]

Abstract: Twelve new organotin complexes with 4-sulfanylbenzoic acid of two types: R n Sn[S(C6H4COOH)]4−n (I) (n =3: R=Me 1, n-Bu 2, Ph 3; PhCH2 4; n =2: R=Me 5; n-Bu 6, Ph 7, PhCH2 8) and R3Sn(SC6H4COO)SnR3 ·mEtOH (II) (m =0: R=Me 9, n-Bu 10, PhCH2 12; m =2: R=Ph 11), along with the 4,4′-bipy adduct of 9, [Me3Sn(SC6H4COO)SnMe3]24,4-bipy) 13, have been synthesized. The coordination behavior of 4-sulfanylbenzoic acid is monodentate in 1–8 by thiol S atom but not carboxylic oxygen atom. While, in 9–13 it behaves as multidenate by both thiol S atom and carboxylic oxygen atoms. The supramolecular structures of 6, 11 and 13 have been found to consist of 1D molecular chains built up by intermolecular O–H⋯O, C–H⋯O or C–H⋯S hydrogen bonds. The supramolecular aggregation of 7 is 2D network determined by two C–H⋯O hydrogen bonds. Extended intermolecular C–H⋯O interactions in the crystal lattice of 9 link the molecules into a 2D network. [Copyright &y& Elsevier]

Abstract: The organotin(IV) complexes R2Sn(tpu)2·L [L=2MeOH, R=Me (1); L=0: R=n-Bu (2), Ph (3), PhCH2 (4)], R3Sn(Hthpu) [R=Me (5), n-Bu (6), Ph (7), PhCH2 (8)] and (R2SnCl)2 (dtpu)·L [L=H2O, R=Me (9); L=0: R=n-Bu (10), Ph (11), PhCH2 (12)] have been synthesized, where tpu, Hthpu and dtpu are the anions of 6-thiopurine (Htpu), 2-thio-6-hydroxypurine (H2thpu) and 2,6-dithiopurine (H2dtpu), respectively. All the complexes 1–12 have been characterized by elemental, IR, 1H, 13C and 119Sn NMR spectra analyses. And complexes 1, 2, 7 and 9 have also been determined by X-ray crystallography, complexes 1 and 2 are both six-coordinated with R2Sn coordinated to the thiol/thione S and heterocyclic N atoms but the coordination modes differed. As for complex 7 and 9, the geometries of Sn atoms are distorted trigonal bipyramidal. Moreover, the packing of complexes 1, 2, 7 and 9 are stabilized by the hydrogen bonding and weak interactions. [Copyright &y& Elsevier]

Two types of di-n-butyltin(IV) complexes {[nBu2Sn(O2CR)]2O}2 · L 1–4 and nBu2Sn(O2CR)2Y 5–8 (when L=H2O, R=2-pyrazine 1; L=0, R=2-pyrimidylthiomethylene 2, 1-naphthoxymethylene 3; L=C6H6, R=2-naphthoxymethylene 4; when Y=H2O, R=2-pyrazine 5; Y=0, R=2-pyrimidylthiomethylene 6, 1-naphthoxymethylene 7, 2-naphthoxymethylene 8) have been prepared in 1:1 or 1:2 molar ratios by reactions of di-n-butyltin oxide with the heteroatomic (N, O or S) carboxylic acids. The complexes 1–8 are characterized by elemental, IR, 1H and 13C NMR spectra. And except for complexes 6 and 7, the complexes 1–5 and 8 are also characterized by X-ray crystallography diffraction analyses, which reveal that the tin atom of complex 5 is seven-coordinated, while the complexes 1–4 and 8 are all hexa-coordinated. The nitrogen atom of the aromatic ring in complexes 1 and 5 participates in the interactions with the Sn atom. [Copyright &y& Elsevier]

A series of organotin(IV) complexes with 2,5-dimercapto-1, 3, 4-thiodiazole (HHdmt) of the type (RnSnClm)2(dmt) (m=0, n=3, R=Ph 1, PhCH2 2, n-Bu 3; m=1, n=2, R=Ph 4) and [R2Sn(dmt) · L]n (L=0.5C6H6, R=CH3 5; L=0, n=5, R=n-Bu 6) have been synthesized. All complexes 1–6 were characterized by elemental analysis, IR, 1H and 13C NMR spectra. And except for 3, complexes 1, 2, 4, 5 and 6 were also determined by X-ray crystallography. The tin atoms of complexes 1, 2, 3 and 4 are all five-coordinated. The geometries at tin atoms of 1, 2, 3 and 4 are distorted trigonal bipyramidal. The tin atoms of complexes 5 and 6 are six-coordinated and their geometries are distorted octahedral. [Copyright &y& Elsevier]

The diorganotin(IV) dichloride reacts with sodium 2-pyridinethiolato-N-oxide in a 1:1 ratio to produce [Me2SnCl(2-SpyO)] (1), [Et2SnCl(2-SpyO)] (2), [Bu2SnCl(2-SpyO)] (3), [Ph2SnCl(2-SpyO)] (4), and [(PhCH2)2SnCl(2- SpyO)] (5). The new complexes have been characterized by elemental analysis and IR and NMR (1H, 119Sn, and 13C) spectroscopy. On the basis of 119Sn NMR data the effective coordination number in solution is five. The structures 1 and 4 have been confirmed by X-ray crystallography. Crystals of 1 are triclinic with space group Pbar over 1 and those of 4 are monoclinic, P21/n. The tin environment is a distorted trigonal bipyramid with the Cl and oxygen atoms in apical positions. Both complexes exhibit strong π–π stacking interactions. [ABSTRACT FROM AUTHOR]

The 18-membered stereoregular diphenyltin macrocycles: {Ph2Sn[S(C6H3NO)O]}3 (8), {Ph2Sn[S(C6H3NO)O]}3·2.67H2O (9) and {Ph2Sn[S(C6H3NO)O]}3·4C6H6 (10) have been synthesized by the reaction of diphenyltin dichloride with 2-mercaptonicotinic acid. The three complexes were characterized by elemental, IR, 1H-NMR analyses. The X-ray crystallography analyses of 9 and 10 were also given. Single crystal X-ray diffraction data reveal that both 9 and 10 are highly symmetrical tri-nuclear cyclic complexes with the ligand 2-mercaptonicotinic acid bridging the adjacent tin atoms. The tin environment is distorted cis-trigonal bipyramid. Weak interaction Sn⋯O was recognized between tin and exocyclic-oxygen atoms. The potential tridentate of endocyclic sulfur atoms make them interesting ligands. [Copyright &y& Elsevier]

The new organotin compound, Ph2Sn(Cl)[S(C7H3N2O2S)]·[(C7H3N2O2S)OEt], assembled by an intermolecular aromatic benzothiazole–benzothiazole π-π stacking interaction, has been synthesized by the reaction of diphenyltin dichloride with 2-mercapto-6-nitrobenzothiazole. The title compound was characterized by elemental, IR, 1H NMR, and X-ray crystallography analyses. Single-crystal X-ray diffraction data reveals that the title compound has two different molecular components. The component Ph2Sn(Cl)[S(C7H3N2O2S)] has a pentacoordinate tin, which further forms an infinite one-dimensional chain by intermolecular non-bonded Cl···S interactions, resulting in an intercalation lattice that holds (C7H3N2O2S)OEt molecules. The formation of the molecule (C7H3N2O2S)OEt as well as its intercalated mechanism has also been discussed. [ABSTRACT FROM AUTHOR]

Characterizing the surface deformation during the inter-survey period could assist in understanding rock mass progressive failure processes. Moreover, 3D reconstruction of rock mass surface is a crucial step in surface deformation detection. This study presents a method to reconstruct the rock mass surface at close range in a fast way using the improved structure from motion—multi view stereo (SfM) algorithm for surface deformation detection. To adapt the unique feature of rock mass surface, the AKAZE algorithm with the best performance in rock mass feature detection is introduced to improve SfM. The surface reconstructing procedure mainly consists of image acquisition, feature point detection, sparse reconstruction, and dense reconstruction. Hereafter, the proposed method was verified by three experiments. Experiment 1 showed that this method effectively reconstructed the rock mass model. Experiment 2 proved the advanced accuracy of the improved SfM compared with the traditional one in reconstructing the rock mass surface. Eventually, in Experiment 3, the surface deformation of rock mass was quantified through reconstructing images before and after the disturbance. All results have shown that the proposed method could provide reliable information in rock mass surface reconstruction and deformation detection. [ABSTRACT FROM AUTHOR]

A novel macrocyclic complex of organotin was synthesized by the reaction of dibutyltin dichloride with 2,5-dimercapto-1,3,4-thiodiazole. The title pentanuclear complex of tin is a 35-membered macrocycle. All five Sn atoms are six-coordinate, and have distorted octahedron geometries due to intramolecular Sn–N interactions. The title complex is characterized by Elemental analysis, IR, 1H-NMR spectroscopy and X-ray diffraction. [Copyright &y& Elsevier]

Luminescent temperature sensors based on photoluminescent materials have received considerable attention for their advantages of quick and noninvasive measurement. In this paper, a series of Tb3+, Eu3+ single-doped and co-doped Ca 2 Al 2 SiO 7 (CAS) phosphors were synthesized by sol-gel method. The phase purity, surface morphology, energy transfer, luminescence characteristics and temperature sensing properties of Tb3+, Eu3+ doped CAS phosphors have been studied carefully. Due to the energy transfer of Tb3+→Eu3+, CAS: Tb3+, Eu3+ phosphors demonstrate tunable luminescence under 238 nm excitation, in which the luminescence color gradually changes from purple-red to cool white, and then to warm white by continuously increasing the concentration of Tb3+ ions. The elongation of the fluorescence lifetime of Eu3+ with increasing Tb3+ ions content further confirms the energy transfer of Tb3+→Eu3+. The thermal behavior of CAS: Tb3+, Eu3+ phosphors shows enhanced luminescence intensity for 404 nm emission while suppressed luminescence intensity for 616 nm emissions with raising temperature, implying its potential in optical temperature sensing. Therefore, the temperature sensing performance is evaluated by using the fluorescence intensity ratio (I 404 nm /I 616 nm) in CAS: Tb3+, Eu3+ phosphors, showing a maximum relative sensitivity of 1.17%K−1 at 443 K. These results indicate that CAS: Tb3+, Eu3+ phosphors are promising candidates for tunable luminescence and non-contact temperature sensing. [ABSTRACT FROM AUTHOR]

Abstract: A series of organotin(IV) complexes with O,O-diethyl phosphoric acid (L1H) and O,O-diisopropyl phosphoric acid (L2H) of the types: [R3Sn·L] n (L=L1, R=Ph 1, R=PhCH2 2, R=Me 3, R=Bu 4; L=L2, R=Ph 9, R=PhCH2 10, R=Me 11, R=Bu 12), [R2Cl Sn·L] n (L=L1, R=Me 5, R=Ph 6, R=PhCH2 7, R=Bu 8; L=L2, R=Me 13, R=Ph 14, R=PhCH2 15, R=Bu 16), have been synthesized. All complexes were characterized by elemental analysis, TGA, IR and NMR (1H, 13C, 31P and 119Sn) spectroscopy analysis. Among them, complexes 1, 2, 3, 5, 8, 9 and 11 have been characterized by X-ray crystallography diffraction analysis. In the crystalline state, the complexes adopt infinite 1D infinite chain structures which are generated by the bidentate bridging phosphonate ligands and the five-coordinated tin centers. [Copyright &y& Elsevier]

Abstract: Three new organotin(IV) carboxylates, {[n-Bu2Sn(O2CC4H4NOS2)]2O}2 (1), n-Bu2Sn(O2CC4H4NOS2)2 (2) and [PhSn(O)O2CC4H4NOS2]6 ·3H2O (3) were synthesized by the reaction of di-n-butyltin/diphenyltin oxide and rhodanine-N-acetic acid. The complexes 1–3 are characterized by elemental, IR, 1H, 13C and 119Sn NMR and X-ray crystallography diffraction analyses. The complex 1 has a tetranuclear structure based on a planar four-membered Sn2O2 ring, while complex 2 is a hexa-coordinated monomer. As for complex 3, it adopts the hexameric drum-shaped structure. The supramolecular structure of 1 has been found to consist of one-dimensional molecular chain built up by intermolecular non-bonded S⋯O interactions. The salient feature of the supramolecular structure of complex 2 is that of a one-dimensional polymer, in which intermolecular Sn⋯O, S⋯O and S⋯S interactions are recognized. [Copyright &y& Elsevier]

Abstract: A series of new organotin (IV) complexes with 3-hydroxy-2-pyridinecarboxylic acid (3-OH-2-picH) of two types: R2SnCl(3-OH-2-pic) (I) (R=Me 1, n-Bu 2, Ph 3, PhCH2 4) and R2 Sn(3-OH-2-pic)2 (II) (R=Me 5, n-Bu 6, Ph 7, PhCH2 8)have been synthesized by reactions of diorganotin (IV) dichloride with 3-hydroxy-2-pyridinecarboxylic acid in the presence of sodium ethoxide. All complexes are characterized by elemental analyses, IR spectra and NMR spectra analyses. Among them, complexes 1, 5, 6 and 7 are also characterized by X-ray crystallography diffraction analyses. Complex 1 is a 1D polymeric chain with six-coordinate tin atoms and the packing of complex 1 is stabilized by the C–H⋯Cl intermolecular weak interactions, thus a 2D network of 1 is formed. Complex 5 is also a 1D polymeric chain with seven-coordinate tin atoms. Complex 6 is a zigzag polymeric chain linked by Sn⋯O intermolecular weak interactions. Complex 7 is a monomeric complex with distorted octahedral geometry. [Copyright &y& Elsevier]

Reaction of tri(o-fluorobenzyl)tin chloride with sodium of heteroaromatic carboxylic acid in 1:1 stoichiometry yielded complexes of the type (2-F-Bz)3SnOOCR (R=2-furanyl, 2-furanvingl, 2-thiophenyl, 2-pyridinyl, 3-pyridinyl, 4-pyridinyl, 3-indolyl, 3-indolmethyl and 3-indolpropyl), respectively. These complexes have been characterized by elemental analyses, IR and 1H NMR spectroscopy. The crystal structures of tri(o-fluorobenzyl)tin esters of 4-pyridinecarboxylic acid (5) and 3-pyridinecarboxylic acid (6) were determined by single crystal X-ray diffraction. In the crystals of compounds 5 and 6, the tin atoms are rendered five-coordinate in a trigonal bipyramidal structure by coordinating with pyridine N atom of carboxylate group. The resulting structure is a one-dimensional linear polymer containing Sn–O bond lengths of 2.161(4), 2.202(9) A˚ and Sn–N bond lengths of 2.518(5), 2.454(10) A˚. [Copyright &y& Elsevier]

Four new organotin complexes, [Me 3 SnO 2 SeC 6 H 4 -F-p] n ( 1 ), [Ph 3 SnO 2 SeC 6 H 4 -F-p] ( 2 ), [Me 2 Sn(O 2 SeC 6 H 4 -F-p) 2 ] n ( 3 ), and [(PhSn) 4 (μ 2 -O) 2 (O 2 SeC 6 H 4 -F-p) 8 ] ( 4 ) have been synthesized via reactions of 4-fluorobenzeneseleninato ligand and the corresponding R 3 SnCl or R 2 SnCl 2 (R = Me, Ph) with sodium ethoxide in methanol. All the complexes have been characterized by X-ray crystallography, elemental analysis, FT-IR, and NMR ( 1 H, 13 C, 119 Sn) spectroscopy. The structural analysis indicates that complex 1 adopts a 1D infinite zigzag chain structure, complex 2 displays a 1D infinite linear polymeric chain structure, complex 3 is 1D helical double-chain polymer containing eight-membered Sn 2 O 4 Se 2 inorganic ring, and complex 4 shows a tetranuclear cage structure containing two Sn–O–Sn motifs connected by bridging [p-F-C 6 H 4 SeO 2 ] - ligands. [ABSTRACT FROM AUTHOR]

Abstract: A mixed tri- and dimethyltin coordination polymer, {[(Me3Sn)(μ2-OH)][Me2Sn(μ3-SCH2CO2)]} (1), has been solvothermally synthesized and structurally characterized by elemental analysis, FT-IR, NMR (1H, 13C, 119Sn) spectra and X-ray crystallography. This complex displays a 1D helical chain structure, in which it can be considered as the tri- and dimethyltin moieties are linked together by the alternate μ2-OH groups and [μ3-SCH2CO2]2− units along the direction. Furthermore, these helical chains are linked together through inter-helix O–H⋯S H-bonding interactions to form a 2D corrugated sheet. [Copyright &y& Elsevier]

• Diorganotin complexes show 2D network containing tetraorganodistannoxane units. • Organotin(IV) carboxylates with n -butyl and phenyl show higher antitumor activity. • Complexes 2 - 3 show lower cytotoxicity than organotin precursors in HBL-100 cells. • Complex 3 can lead to depolarization of mitochondrial membrane potential. • Complex 3 could induce cellular reactive oxygen species accumulation. Seven organotin(IV) complexes, [(R 3 Sn) 2 L] n (R = Me 1 , R = n -Bu 2), [(Ph 3 Sn) 2 L] (3), [(R 2 Sn) 2 L(μ 3 -O)] n (R = Me 4 , R = n -Bu 5), [R 2 SnL(1,10-phen)] n (R = Me 6), [(R 2 SnCl) 2 L(1,10-phen) 2 ] (R = n -Bu 7) derived from 1,4-naphthalenedicarboxylic acid (H 2 L) have been synthesized and characterized by elemental analysis, FT-IR, PXRD, NMR and X-ray crystallography. The single crystal diffraction reveals that complexes 1 and 2 represent 2D network structures, which both contain tetranuclear 26-membered macrocycles. Complexes 3 and 7 display dinuclear tin monomers, which can form 1D infinite chain by C-H ··· O and C-H ··· π interactions. Meanwhile, complexes 4 and 5 display 2D network containing tetraorganodistannoxane unit, while complex 6 adopts a 1D infinite chain structure, which further constructs 2D supramolecular architecture through C-H ··· O intermolecular interactions. What's more, in vitro cytostatic activity of the complexes 1 - 3 against cervical carcinoma cell lines (HeLa), hepatocellular carcinoma cell lines (HepG-2) and human normal breast cell lines (HBL-100) have been investigated, and the results show that organotin derivatives with n -butyl and phenyl group (2 and 3) exhibit significantly higher anticancer activity than complex 1 with methyl group. Meanwhile, organotin(IV) complexes (1 - 3) display lower cytotoxicity than corresponding organotin(IV) precursors [trimethyltin chloride, bis(tri- n -butyltin) oxide and triphenyltin chloride] in HBL-100 cells. Furthermore, cytostatic assessments of complex 3 against HepG-2 cells reveal that the effect of cytostatic and apoptotic may through ROS-mediated pathway. Image, graphical abstract [ABSTRACT FROM AUTHOR]

A series of Sr 3 La 2 (PO 4) 2 (SiO 4)O: Eu2+ phosphors were synthesized by conventional high-temperature solid-state reaction. The phase formation was confirmed by XRD analysis. The photoluminescence properties of Sr 3 La 2 (PO 4) 2 (SiO 4)O: Eu2+ phosphors were investigated systematically. The phosphors exhibit absorption in the ultraviolet–visible spectral region of 280–420 ​nm and show an intense asymmetric broadband blue emission peaking at 454 ​nm under the excitation at 365 ​nm. The concentration quenching mechanism, decay property, and thermal stability have been discussed in detail. The investigation results indicate that Sr 3 La 2 (PO 4) 2 (SiO 4)O: Eu2+ will have applications as the blue component in tricolor near-ultraviolet pumped white light-emitting diodes. The Sr 3 La 2 (PO 4) 2 (SiO 4)O: Eu2+ phosphor was reported, which shows the potential application as a blue component in tricolor n-UV pumped wLEDs. Image 1 [ABSTRACT FROM AUTHOR]