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A series of solid ternary lanthanide complexes with the general formula Ln(BA)3(PIP) (Ln = La–Lu, except Pm) were prepared with hydrated lanthanide chloride, benzoic acid (BA), and 2-phenylimidazo[4,5-f]1,10-phenanthroline (PIP). These obtained complexes were characterized by means of elemental analysis, EDTA volumetric analysis, IR spectroscopy, X-ray powder diffraction, and mass spectroscopy. The thermal decomposition mechanism of all complexes in the solid state was explored using TG–DTG techniques under dynamic flow of air atmosphere. Moreover, the constant-volume combustion energies, ∆c U, of the complexes were determined by a precise rotating-bomb calorimeter (RBC-type II) at 298.15 K. Their standard molar enthalpies of combustion, $$ \Delta _{\text{c}} H_{\text{m}}^{\uptheta} $$ , and standard molar enthalpies of formation, $$ \Delta_{\text{f}} H_{\text{m}}^{\uptheta} $$ , were calculated.

Hydrothermal synthesis and X-ray characterized 3D supramolecular networks were constructed by [Co(HnicO)2·(H2O)2] (HnicOH=2-hydroxynicotinic acid) (1) as building block via abundant dimeric homomeric (N–H···O) and unusually cyclic tetrameric heteromeric (O–H···O) hydrogen-bonds. It is noted that there exist unusually linear metal-water chains comprised of tetrameric units linked by vertexes sharing cobalt centers through hydrogen-bonding. TG-DTG curves illustrated that thermal decomposition was completed by two steps, one is the loss of two terminal water molecules in the range of 156–234 °C, and the other is the pyrolysis of HnicO ligand in the range of 234–730 °C. The standard molar enthalpy of formation of the complex was determined to be (−1845.43±2.77) kJ·mol−1 by a rotary-bomb combustion calorimeter.

The constant-volume combustion energy, ΔcU (DADE, s, 298.15 K), the thermal behavior, and kinetics and mechanism of the exothermic decomposition reaction of 1,1-diamino-2,2-dinitroethylene (DADE) have been investigated by a precise rotating bomb calorimeter, TG-DTG, DSC, rapid-scan fourier transform infrared (RSFT-IR) spectroscopy and T-jump/FTIR, respectively. The value of ΔcH⊖m (DADE, s, 298.15 K) was determined as (−8518.09± 4.59) J·g−1. Its standard enthalpy of combustion, ΔcU (DADE, s, 298.15 K), and standard enthalpy of formation, ΔfH⊖m (DADE, s, 298.15 K) were calculated to be (−1254.00±0.68) and (−103.98±0.73) kJ·mol−1, respectively. The kinetic parameters (the apparent activation energy Ea and pre-exponential factor A) of the first exothermic decomposition reaction in a temperature-programmed mode obtained by Kissinger′s method and Ozawa′s method, were Ek=344.35 kJ·mol−1, Ak=1034.50 s−1 and Eo=335.32 kJ·mol−1, respectively. The critical temperatures of thermal explosion of DADE were 206.98 and 207.08 °C by different methods. Information was obtained on its thermolysis detected by RSFT-IR and T-jump/FTIR.

Two complexes, {Zn(bptc)0.5(bib)}n (I) and {Mn2(bptc)(pip)(H2O)}n (II) (H4bptc = biphenyl-3,3′,5,5′-tetracarboxylic acid; bib = 1,4-bis(2-methylimidazol-1-yl)butane; pip = 2-phenyl-1H-imidazo[4,5-f][1,10]phenanthroline) were synthesized and characterized by single-crystal X-ray diffraction, elemental analysis, IR, TGA and solid fluorescence spectra. The results show that I and II both have 3D network architectures. I has porous architecture with a 162 topology structure. Effective porosity calculated by Platon is 5.5 %. Moreover, it has a two-fold interpenetrating structure allowed by a 70.73° torsion between the benzene rings of the bptc4− ligand and the flexibility of bib. II has a tetranuclear structure composed of binuclear architecture units with the torsion of 43.44° between the benzene rings of the bptc4− ligand. TGA shows that the skeletons of I and II are stable up to 372°C and 553°C, respectively. I exhibits fluorescence.

The constant-volume combustion energies have been determined for three kinds of crown ether (CE) using a precision rotating-bomb calorimeter (RBC). The standard enthalpies of combustion, ΔcCEHθ, and standard enthalpies of formation, ΔfCEHθ, have been calculated for these CE. Two empirical formulas have been proposed about the standard combustion enthalpies of aromatic CE.

Combustion energies have been determined for 13 amino acids (Glycine, dl -Alanine, dl -Butyric acid, l -Aspurtic acid, l -Serine, l -Lysine, l -Glutamic acid, l -Arginine, l -Histidine, l -Tyrosine, dl -Phenylalanine, l -Cystine, l -Methioine) using a rotating-bomb calorimeter. The corresponding standard enthalpies of combustion, Δ c,Am(s) H θ , and the standard enthalpies of formation, Δ f,Am(s) H θ , have been calculated. The reliability of the results is illustrated through comparing with the values in references.

The eight solid complexes of zinc with l -α-methionine or l -α-histidine were prepared. The constant-volume combustion energies of the complexes, Δ c,coor E , at 298.15 K have been determined by using a precision rotating-bomb calorimeter. The standard enthalpies of combustion, Δ c,coor H θ , and standard enthalpies of formation, Δ f,coor H θ , have been calculated for these complexes.

The combustion energies have been determined for fifteen solid complexes of rare-earth nitrate with histidine.The standard enthalpies of combustion, Δ c,coor H θ , and standard enthalpies of formation, Δ f,coor H θ , have been calculated for these complexes. The relationship of Δ f,coor H θ with the atomic numbers of the elements in the lanthanide series has been examined. The results show that a certain amount of covalence is present in the chemical bond between the rare-earth cations and histidine.

Combustion energies have been determined for the 24 solid complexes of rare-earth chlorides with DL–alanine: RE(Ala)Cl 3 ·6H 2 O (I) (RE=Eu–Ho, Yb, Y), RE(Ala) 2 Cl 3 · n H 2 O (II) (RE=La–Nd, Sm, n =3; RE=Ho, Yb, Y, n =4) and RE(Ala) 3 Cl 3 ·3H 2 O (III) (RE=La–Nd, Sm–Dy). The standard enthalpies of combustion, Δ c,coor H 0 , and standard enthalpies of formation, Δ f,coor H 0 , have been calculated for these complexes. The relationship of Δ f,coor H 0 with the ionic radius of rare- earth cations has been examined. The results show that a certain amount of covalence is present in the chemical bond between the rare-earth cation and DL–alanine.

The combustion energies have been determined for the thirteen solid complexex of rare earth nitrates with glycine. The standard enthalpies of combustion, Δ c,(coor) H ⊖ , and standard enthalpies of formation, Δ f,(coor) H ⊖ , have been calculated for these complexes. The relationship of Δ f,(coor) H ⊖ with the atomic numbers of the elements in the lanthanide series has been examined. The results show that a certain amount of covalency is present in the chemical bond between the rare earth cation and glycine.

Two complexes, {[Cd6(o-dppd)2(µ2-Cl)6(µ3-Cl)2(DMF)2(H2O)2Cl2]·DMF·CH3OH}n (I) (DMF = N,N-dimethylformamide; o-dppdH = 1,3-di(pyridin-2-yl)propane-1,3-dione) and [Cu4(o-dppd)2(OAc)4(OH)2]·4H2O (II), were synthesised and characterised by single-crystal X-ray diffraction, elemental analysis, IR, solid fluorescence and TGA. The results showed that complex I had a rodshaped polynuclear chain with hexacoordinating Cd atoms bridged by oxygen, µ2-Cl and µ3-Cl; complex II was a tetranuclear oligomer. In general, supramolecular architectures are constructed through hydrogen-bonding and π-π stacking interactions. I shows luminescence.

A new complex, [Cu2(μ 2-Cl)2(IP)2Cl2] · 4H2O (IP = imidazo[4,5-f]1,10-phenathroline), was synthesised and characterised by elemental analysis, thermal analysis, IR spectra, and X-ray crystallography. The results showed that the complex crystallises in the monoclinic space group P $$ \bar 1 $$; a = 7.880 (2) Å, b = 9.227(2) Å, c = 10.694(2) Å; α = 97.788(4)°, β = 100.637(4)°, γ = 95.841(3)°; V = 750.7(3) Å3, and Z = 1. The complex is further stabilised by H-bonds and a π-π stacking interaction between the pyridine and benzene rings of two neighbouring molecules with the centroid.centroid distance of 3.498(3) Å, leading to a 3D supramolecular architecture. Thermal decomposition procedure of the complex explored by TG-DTG has three stages, and the final product is Cu in residual rate of 16.18 % (calculated to be 16.26 %).

The ternary solid complexes RE(Et2dtc)3 (phen) (RE=La, Pr, Nd, Sm-Er) were synthesized with sodium diethyldithiocarbamate (NaEt2 dtc x 3H2O), 1,10-phenanthroline (o-phen x H2O) and hydrated lanthanide chlorides in absolute ethanol by improved reported method. IR results revealed that RE3+ coordinated with sulfur atoms of NaEt2 dtc and nitrogen atoms of o-phen. As for UV spectrum of the complexes, energy transfer between o-phen and RE3+ was the primary process, and the main absorption peaks showed a slight red shift compared to that of o-phen; FS spectrum, as a comparison, showed that the complexes Sm (Et2 dtc)3 (phen) and Eu(Et2dtc)3 (phen) have a higher efficiency of intermolecular energy transfer and a stronger fluorescence character.