The ternary solid complex has been synthesized with sodium diethyldithiocarbamate (NaEt2dtc?3H2O), 1,10-phenanthroline (o-phen?H2O) and hydrated neodymium chloride in absolute ethanol. The title complex was identified as the general formula of Nd(Et2dtc)3(phen) by chemical and elemental analyses. IR spectrum of the complex showed that the Nd3+ coordinated with six sulfur atoms of three NaEt2dtc and two nitrogen atoms of o-phen. It was assumed that the coordination number of Nd3+ is eight.The enthalpy change of liquid-phase reaction of formation, ?rHm (l), was determined as (-12.274±0.050) kJ?mol-1 at 298.15 K by a microcalorimeter, the Θ enthalpy change of the solid-phase reaction of formation, ?rHm (s), was calculated as (149.069±0.314) kJ?mol-1 Θ on the basis of a thermochemical cycle. The thermodynamics of reaction of formation was studied by changing the temperature of liquid-phase reaction. The constant-volume combustion energy of the complex, ?cU , was deter- mined as (-18674.22±8.33) kJ?mol-1 by a precise rotating-bomb calorimeter at 298.15 K. Its standard enthalpy of combustion, ?cHm , and standard enthalpy of formation, ?fHm , were calculated as (-18693.43±8.33) kJ?mol-1 Θ Θ and (-47.03±9.17) kJ?mol-1, respectively.
The treatment of RECl3.xH2O （RE = Ho, Er, Tm, Yb, Lu; x = 3-4） with sodium diethyldithiocarbamate （NaEtEdtc-3H2O） and 1,10-phenanthroline hydrate （o-phen.H2O） in absolute ethanol yielded five ternary solid complexes RE（EtEdtC）a（phen）. IR spectra of the complexes showed that RE^3＋ coordinated to two sulfur atoms in NaEt2dtc and two nitrogen atoms in o-phen. The constant-volume energies of combustion of the complexes have been determined by a precise rotating-bomb calorimeter at 298.15 K. The standard enthalpies of combustion and standard enthalpies of formation were calculated.
WEI Qing CHEN Sanping YANG Xuwu GAO Shengli SHI Qizhen
Amino 4,6 dimethoxypyrimidine(AMP) was synthesized using benzyltriethyl ammonium chloride(BTEA) as a catalyst in yield of 87 5%. A solid complex Co(AMP) 2Cl 2 was obtained by refluxing AMP with CoCl 2 in ethanol. The composition of the complex was determined by chemical and elemental analyses. The structure of the complex and sp 3 d 2 of the hybridization type of Co 2+ were estimated by IR, XPS and 1H NMR.
The complex of samaric chloride lower hydrate with diethylammoniumdiethyldithiocarbamate (D-DDC) was synthesized conveniently in absolute alcohol and dry N_2atmosphere. The title complex was identified as Et_2NH_2[Sm(S_2CNEt_2)_4] by chemical and elementalanalyses, the bonding characteristics of which was characterized by IR. The enthalpies of solutionof samaric chloride hydrate and D-DDC in absolute alcohol at 298.15 K and the enthalpies change ofliquid-phase reaction of formation for Et_2NH_2[Sm(S_2CNEt_2)_4] at different temperatures weredetermined by mi-crocalorimetry. On the basis of experimental and calculated results, threethermodynamic parameters (the activation enthalpy, the activation entropy, and the activation freeenergy), the rate constant, and three kinetic parameters (the apparent activation energy, thepre-exponential constant, and the reaction order) of liquid phase reaction of formation wereobtained. The enthalpy change of the solid-phase title reaction at 298.15 K was calculated by athermochemical cycle.
The pale blue powder of copper Lthreonac was obtained by extracting with alcohol in the concentrated solution derived from the reaction between Lthreonate acid solution prepared by double decomposition reaction of calcium Lthreonate with oxalic acid and superfluous copper dihydrocarbonate at 80℃ and 30 min.The composition of the new compound was determined by chemical and elemental analyses and its formula fits Cu(C4H6O5)·05H2O.The IR spectra indicated that Cu2+ in the compound coordinates to oxygen atom of the carboxyl group pentaring and oxygen atom of hydroxy group of ethanol attached to carboxyl group forming,while the proton of the carboxyl group is dissociated.The results of TG-DTG show that the compound has fairish stability,the intermediate and final product of the thermal decomposition of the compound are Cu(C4H6O5) and CuO ,respectively.The constant volume combustion energy of the compound,ΔcE,it is (-16165±072)kJ·mol-1,was determined by a precise rotatingbomb calorimeter at 29815K,and its standard enthalpy of combustion,ΔcHθm,and standard enthalpy of formation,ΔfHθm,were calculated.They are(-161491±072)kJ·mol-1and (-111476±081)kJ·mol-1,respectively.
The enthalpy change of formation of the reaction of hydrous dysprosium chloride meter. Thermodynamic parameters (the activation enthalpy, the activation entropy and the activation free energy), rate constant and kinetics parameters (the apparent activation energy, the pre-exponential constant and the reaction order) of the reaction have also been calculated. The enthalpy change of the solid-phase reaction at 298.15 K has been obtained as (53.59 ± 0.29)liquid-phase and solid-phase reaction indicated that the complex could only be synthesized in liquid-phase reaction.
GAO Shengli CHEN Sanping JIAO Baojuan SHUAI Qi SHI Qizhen
The thermal behavior of the complex Pr[(C5H8NS2)3(C12H8N2)] in a dry nitrogen flow was examined by TG-DTG analysis. The TG-DTG investigations indicated that Pr[(C5H8NS2)3-(C12H8N2)] was decomposed into Pr2S3 and deposited carbon in one step where Pr2S3 predominated in the final products. The results of non-isothermal kinetic calculations showed that the decomposition stage was the random nucleation and subsequent growth mechanism (n = 2/3), the corresponding apparent activation energy ?was 115.89 kJ·mol-1 and the pre-expo-nential constant ln[A/s] was 7.8697. The empirical kinetics model equation was proposed as/(α) =3/2(1-α)[-ln(1-α)]1/3.The X-ray powder diffraction patterns of the thermal decomposition products at 800℃under N2 atmosphere show that the product can be indexed to the cubic Pr2S3 phase. The transmission electron microscopy (TEM) of the final product reveals the particle appearance of a diameter within 40 nm. The experimental results show that the praseodymium sulfide nanocrystal can be prepared from thermal decomposition of Pr[(C5H8NS2)3(C12H8N2)].
GUO Pengjiang,JIAO Baojuan,CHEN Sanping,HU Rongzu,GAO Shengli & SHI Qizhen Department of Chemistry,Northwest University
