, 16 ]. Recently, it has been greatly developed for directly determining heat capacities for various materials successfully [ 17 – 20 ].
In this article, the preparation and the crystalstructure of DPFEB were reported. In addition, the molar
Authors:Y. P. Liu, Y. Y. Di, W. Y. Dan, and D. H. He
researches are focused on phase transitions of (1-C 12 H 25 NH 3 ) 2 CuCl 4 , (1-C 14 H 29 NH 3 ) 2 CuCl 4 , and (1-C 16 H 33 NH 3 ) 2 CuCl 4 . However, the crystalstructure, lattice potential energy, and some basic thermochemical data of (1-C 8 H 17 NH 3
Authors:Timo Hatanpää, Kaupo Kukli, Mikko Ritala, and Markku Leskelä
thermal analysis (SDTA) measurements and vacuum sublimation experiments. Crystalstructures of four new compounds, [Y(OCEt 2 t Bu) 3 ] 2 , [La(OCEt 2 t Bu) 3 ] 2 , [Gd(OC i Pr 3 ) 3 ] 2 , and [La(OC i Pr 3 ) 3 ] 2 were solved. In addition, some ALD
’s group at Clemson University, in order to correlate CNT’s crystalstructure and chemical activity [ 6 ]. In addition, for the first time, molecular beam scattering data have been collected on CNTs in collaboration with Turro’s group at Columbia University
Authors:H. Ye, N. Ren, H. Li, J. Zhang, S. Sun, and L. Tian
The complex of [Nd(BA)3bipy]2 (BA = benzoic acid; bipy = 2,2′-bipyridine) has been synthesized and characterized by elemental analysis, IR spectra, single
crystal X-ray diffraction, and TG/DTG techniques. The crystal is monoclinic with space group P2(1)/n. The two–eight coordinated Nd3+ ions are linked together by four bridged BA ligands and each Nd3+ ion is further bonded to one chelated bidentate BA ligand and one 2,2′-bipyridine molecule. The thermal decomposition process
of the title complex was discussed by TG/DTG and IR techniques. The non-isothermal kinetics was investigated by using double
equal-double step method. The kinetic equation for the first stage can be expressed as dα/dt = A exp(−E/RT)(1 − α). The thermodynamic parameters (ΔH≠, ΔG≠, and ΔS≠) and kinetic parameters (activation energy E and pre-exponential factor A) were also calculated.
Authors:Bao-Di Xue, Qi Yang, San-Ping Chen, and Sheng-Li Gao
A new high-nitrogen complex [Cu(Hbta)2]·4H2O (H2bta = N,N-bis-(1(2)H-tetrazol-5-yl) amine) was synthesized and characterized by elemental analysis, single crystal X-ray diffraction
and thermogravimetric analyses. X-ray structural analyses revealed that the crystal was monoclinic, space group P2(1)/c with lattice parameters a = 14.695(3) Å, b = 6.975(2) Å, c = 18.807(3) Å, β = 126.603(1)°, Z = 4, Dc = 1.888 g cm−3, and F(000) = 892. The complex exhibits a 3D supermolecular structure which is built up from 1D zigzag chains. The enthalpy change
of the reaction of formation for the complex was determined by an RD496–III microcalorimeter at 25 °C with the value of −47.905 ± 0.021 kJ mol−1. In addition, the thermodynamics of the reaction of formation of the complex was investigated and the fundamental parameters
k, E, n,
were obtained. The effects of the complex on the thermal decomposition behaviors of the main component of solid propellant
(HMX and RDX) indicated that the complex possessed good performance for HMX and RDX.
Authors:W. Dan, Y. Di, Y. Kong, Q. Wang, W. Yang, and D. Wang
The complex (C11H18NO)2CuCl4(s) was synthesized. Chemical analysis, elemental analysis, and X-ray crystallography were used to characterize the structure
and composition of the complex. Low-temperature heat-capacities of the compound were measured by an adiabatic calorimeter
in the temperature range from 77 to 400 K. A phase transition of the compound took place in the region of 297–368 K. Experimental
molar heat-capacities were fitted to two polynomial equations of heat-capacities as a function of the reduced temperature
by least square method. The peak temperature, molar enthalpy, and entropy of phase transition of the compound were calculated
to be Ttrs = 354.214 ± 0.298 K, ΔtrsHm = 76.327 ± 0.328 kJ mol−1, and ΔtrsSm = 51.340 ± 0.164 J K−1 mol−1.
Crystal structures together with enthalpies and temperatures of fusion of two substituted amino acids, N-acetylsarcosinamide (NASarA) and N-acetyl-L-isoleucinamide (NAIA), were determined by single crystal X-ray analysis and differential scanning calorimetry, respectively. The results were compared with those of some analogous amino acid derivatives previously studied. The detailed knowledge of crystallographic parameters is undoubtedly useful for discussing the thermodynamic results and rationalizing the fusion behaviour, owing to the rather poor knowledge of the molecular interactions occurring in the melt.
The effect of certain promoters on TiO2 crystal structure transformation was studied by mean thermal and X-ray analyses. It was found that the addition of rutile nuclei and potassium, phosphorus, zinc, magnesium, and aluminium compounds to hydrated titanium dioxide before calcination process influences on the initial temperature and anatase transformation.
The results of theoretical analysis of the crystal structure and bonding in relation to thermal decomposition process in anhydrous
mercury oxalate are presented. The methods used Bader’s Quantum Theory of Atoms in Molecules formalism with bond order model
(by Cioslowski and Mixon), applied to electron density obtained from ab initio calculations carried out with FP-LAPW Wien2k
package (Full Potential Linearized Augmented Plane Wave Method) and Brown’s Bond Valence Model are described. The analysis
of the obtained results shows that most probably the thermal decomposition process of mercury oxalate should lead to metal
and CO2 as products (as it is experimentally observed). Presented results (as well as the results of our similar calculations carried
out previously for zinc, cadmium silver, cobalt and calcium oxalates) allow us to state that such methods (topological and
structural), used simultaneously in analysis of the crystal structure and bonding properties, provide us with the additional
insight into given compound’s behavior during thermal decomposition process. As a result, these methods can be considered
as valuable supporting tool in the analysis of thermal decomposition process in given compound.