三元配合物Dy（Et2dtc）3（phen）的热化学性质

以铜试剂(NaEt2dtc·3H2O)和菲咯啉(phen·H2O)与低水合氯化狄(DyCl3·3.74H2O)在无水乙醇中反应,制得三元固态配合物,化学分析和元素分析确定该化合物的组成为Dy(Et2dtc)3(phen)。IR光谱表明配合物中Dy3 与3个NaEt2dtc中的6个硫原子双齿配位,同时与phen中的2个氮原子双齿配位,可推测其配位数为8。用微热量计测定出298.15 K下液相生成反应的焓变A,H曼(1)为(一19.091±0.015)kJ·mol_。,通过合理的热化学循环计算出固相生成反应焓变△rHmθ(s)为(139.641±0.482)kJ·mol-1;改变反应温度,研究了配合物的液相生成反应的热动力学,配合物的恒容燃烧能△cU用精密转动弹热量计测定为(-16730.21±9.25)kJ·mol-1,其标准燃烧焓△fHmθ和标准生成焓△fHmθ经计算分别为(-16749.42±9.25)kJ·mol-1和(-2019.68±10.19)kJ·mol～1。     

三元配合物Ho(Et2dtc)3(phen)的合成及其热化学性质

改进文献方法,以铜试剂(NaEt2dtc·3H2O)和邻菲咯啉(o-phen·H2O)与低水合氯化钬(HoCl3·3.58H2O)在无水乙醇中反应,制得三元固态配合物.化学分析和元素分析确定该配合物的组成为Ho(Et2dtc)3(phen).IR光谱表明配合物中Ho3 与3个NaEt2dtc中的6个硫原子双齿配位,同时与o-phen中的2个氮原子双齿配位,可推测其配位数为8.用微量热量计测定了298.15 K下液相生成反应的焓变△rHm (1),为(-14.697±0.0376)kJ·mol-1,通过合理的热化学循环计算了固相生成反应焓变△rHm (s),为(117.504±0.619)kJ·mol-1;改变反应温度,研究了配合物的液相生成反应的热力学性质.配合物的恒容燃烧能△cU用精密转动弹热量计测定为(-18687.64±8.22)kJ·mol-1,其标准燃烧焓△cHm 和标准生成焓△fHm 经计算分别为(-18706.85±8.22)和(-70.01±9.37)kJ·mol-1.     

稀土脯氨酸配合物[RE2(L-Pro)6(H2O)4](ClO4)6的标准生成焓测定

合成了两种稀土高氯酸盐与L 脯氨酸配合物的晶体.经热重、差热、化学分析及对比有关文献,知其组成是[Pr2(L Pro)6(H2O)4](ClO4)6和[Er2(L Pro)6(H2O)4](ClO4)6,质量分数为99.24％和98.20％.选用RE(NO3)3•6H2O(RE=Pr,Er)、L Pro、NaClO4•H2O和NaNO3作辅助物,使用具有恒温环境的反应热量计,以2 mol•L－1 HCl作溶剂,分别测定了[2RE(NO3)3•6H2O＋6L Pro＋6NaClO4•H2O]和{[RE2(L PrO)6(H2O)4](ClO4)6＋6NaNO3}在298.15 K时的溶解热.设计一热化学循环求得化学反应的反应焓ΔrHm分别是：63.904 kJ•mol－1和91.017 kJ•mol－1,经计算得配合物[RE2(L Pro)6(H2O)4](ClO4)6(s)在298.15 K时的标准生成焓ΔfHm(298.15 K)分别是－6 594.78 kJ•mol－1和－6 532.87 kJ•mol－1.     

L-苏糖酸镁的制备及标准生成焓

以L-苏糖酸钙与草酸的复分解反应得到的L-苏糖酸溶液，在80 ℃下与过量MgO反应较长时间， 滤液浓缩后加无水乙醇制得L-苏糖酸镁白色粉末.用化学分析及元素分析确定其组成为Mg(C4H7O5)2•H2O. IR光谱分析表明,化合物中苏糖酸以羧基氧原子与Mg2＋配位，Mg2＋为sp3杂化态，配位数为4. TD－DTG结果说明，它在热分解中有一定稳定性，而经脱水和生成Mg(OAc)2，最后生成MgO.用转动弹热量计测得其恒容燃烧能ΔE为 (－10407.34±4.67) kJ•mol－1,计算其标准燃烧焓ΔcHm和标准生成焓ΔfHm分别为(－3 249.49±1.46) kJ•mol－1和(－2 786.23±1.84) kJ•mol－1.     

Zn(Thr)Ac2•2H2O固态配合物的制备及标准生成焓

在水-丙酮混合溶剂中合成了未见文献报导的Zn(Thr)Ac2•2H2O固态配合物,通过化学分析、元素分析、IR、XRD和TG-DTG等对其组成、结构及热稳定性进行了研究.用微量热法测定了配合物在298.15 K时在纯水中的溶解焓,计算了Zn(Thr)2＋(aq,∞)和Zn(Thr)Ac2•2H2O(s) 的标准摩尔生成焓分别为(955.24±5.70) kJ•mol－1和(-570.92±5.71) kJ•mol－1.     

水杨醛-1H-苯并三唑-1-乙酰腙与镧(Ⅲ)配合物的制备、表征及热化学

在甲醇中,利用水杨醛-1H-苯并三唑-1-乙酰腙(C15H13N5O2,简称SBTH)与高氯酸镧反应,制得一新配合物,经元素分析、化学分析并结合热分析确定了其组成为La(C15H12N5O2)( C15H11N5O2)•2.5H2O.利用电导测定、红外光谱、1H NMR和TG-DTG等手段推测了配合物的结构.用微热量计测定了配合物在不同浓度(b)时的溶解焓,用计算机拟合求得该配合物的标准摩尔溶解焓(ΔsolHmΘ=－135.62 kJ•mol－1)及溶解焓(ΔsolH)的经验公式(ΔsolH=－135.62－11633b＋3761.5b1/2),并由此分别推导出配合物的相对表观摩尔焓(Li)、相对偏摩尔焓(Li)以及配合物稀释焓(ΔdilH1,2)的经验公式:Li=－11633b＋3761.5b1/2；Li=－23266b＋5642.2b1/2和ΔdilH1,2=－11633(b21/2－b11/2)＋3761.5(b2－b1).还研究了配合物的热分解过程,利用Kissinger公式计算了配合物主要分解阶段的表观活化能(Ea=470.24 kJ•mol－1).     

硝酸镝与丙氨酸配位反应的热化学研究

采用新型的具有恒温环境的反应热量计 ,以 2mol L的HCl作溶剂 ,分别测定了 [Dy(NO3) 3·6H2 O +4Ala]和Dy(Ala) 4(NO3) 3·H2 O在 2 5℃时的溶解焓。通过设计的热化学循环得到六水硝酸镝与丙氨酸配位反应的反应焓ΔrHmθ=30 .638kJ mol,并计算出配合物Dy(Ala) 4(NO3) 3·H2 O在 2 98.1 5K时的标准生成焓ΔfHmθ=-3833.8kJ mo     

L－苏糖酸钴的制备及标准生成焓

以L－苏糖酸钙与草酸的复分解反应得到的L－苏糖酸溶液，在80℃下与过量 CoO反应较长时间，滤液浓缩后加无水乙醇制得L－苏糖酸钴粉红色粉末。用化学分 析及元素分析确定其组成为Co(C4H7O5)·H2O,IR光谱分析结果表明新化合物中苏糖 酸以羧基氧原子与Co^+配位。TD－DTG结果说明，它在热分解中有一定稳定性，经 脱水生成Co-(C4H7O5)2,最后生成CoO。用转动弹热量计测得其恒容燃烧能ΔcE为（ －3504.47±1.64)kJ·mol^-1，计算得其标准燃烧焓和标准生成焓ΔfHm^θ分别为 （－3501．99±1．64）和（－2170．67±1.97)kJ·mol^-1。     

三元配合物Er(Et2dtc)3(phen)的热化学性质

三元配合物Er(Et2dtc)3(phen)的热化学性质;Er(Et2dtc)3(phen); 微量热法; 热动力学; 恒容燃烧能; 标准摩尔生成焓     

三元配合物RE(Et2dtc)3(phen)热化学性质的规律性

在无水乙醇中, 用铜试剂(NaEt₂dtc•3H₂O)和邻菲咯啉(o-phen•H₂O)分别与13种低水合氯化稀土合成了三元固态配合物(其中5种尚未见文献报道), 确定它们的组成可用通式RE(Et₂dtc)₃(phen)表示. IR光谱表明配合物中RE³⁺与3个NaEt₂dtc中的6个硫原子双齿配位, 同时与o-phen中的2个氮原子双齿配位. 用RD496-Ⅲ微量热计测定了298.15 K下13种水合氯化稀土盐及两个配体在无水乙醇中的溶解焓, 两个配体醇溶液的混合焓及13种化合物液相生成反应的焓变, 并通过合理的热化学循环, 求得了标题配合物的固相生成反应焓变; 测定了标题配合物298.15 K的比热容. 用RBC-II精密转动弹热量计测定了标题配合物的恒容燃烧热, 计算了它们的标准摩尔燃烧焓和标准摩尔生成焓. 发现系列配合物RE(Et₂dtc)₃(phen) (RE＝La, Pr, Nd, Sm～Lu)的多项热化学性质, 如低水合氯化稀土盐在无水乙醇中的溶解焓以及配合物的液相生成反应焓变和固相生成反应焓变、常温比热容、标准摩尔燃烧焓和标准摩尔生成焓都与稀土原子序数作图呈现“三分组现象”. 较集中地反映出配合物中RE³⁺与配体间的化学键有一定程度的共价性, 这是由于稀土离子5s²5p⁶轨道对4f电子的不完全屏蔽引起的.     

Lu(Et2dtc)3(phen)的生成反应焓变、摩尔热容和恒容燃烧能测定

A ternary solid complex Lu(Et₂dtc)₃(phen) has been obtained from the reaction of hydrated lutetium chloride with sodium diethyldithiocarbamate (NaEt₂dtc), and 1,10-phenanthroline (o-phen·H₂O) in absolute ethanol. IR spectrum of the complex indicates that Lu³⁺ binds with sulfur atom in the Na(Et₂dtc)₃ and nitrogen atom in the o-phen. The enthalpy change of liquid-phase reaction of formation of the complex, Δ_rH_m^Ө (l), was determined to be (-32.821 ± 0.147 ) kJ·mol^-1 at 298.15 K by an RD-496 Ⅲ type heat conduction microcalormeter. The enthalpy change of the solid-phase reaction of formation of the complex, Δ_rH_m^Ө (s), was calculated to be (104.160 ± 0.168) kJ · mol^-1 on the basis of an appropriate thermochemistry cycle. The thermodynamics of liquid-phase reaction of formation of the complex was investigated by changing the temperature of liquid-phase reaction. Fundamental parameters, such as the activation enthalpy (ΔH_≠^Ө), the activation entropy (ΔS_≠^Ө), the activation free energy (ΔG_≠^Ө), the apparent reaction rate constant (k), the apparent activation energy (E), the pre-exponential constant (A) and the reaction order (n), were obtained by combination the reaction thermodynamic and kinetic equations with the data of thermokinetic experiments. The molar heat capacity of the complex, c_m, was determined to be (82.23 ± 1.47) J·mol^-1·K^-1 by the same microcalormeter. The constant-volume combustion energy of the complex, Δ_cU, was determined as (-17 898.228 ± 8.59) kJ·mol^-1 by an RBC-Ⅱtype rotating-bomb calorimeter at 298.15 K. Its standard enthalpy of combustion, Δ_cH_m^Ө, and standard enthalpy of formation, Δ_fH_m^Ө, were calculated to be (-17 917.43 ± 8.11) kJ·mol^-1 and (-859.95 ±10.12) kJ·mol^-1, respectively.     

RE(Et2dtc)3(phen)(RE=La，Pr，Nd，Sm)的恒容燃烧能测定(英)

Four ternary solid complexes were synthesized with sodium diethyldithiocarbamate (NaEt₂dtc)(b), 1,10-phenanthroline (o-phen) (c) and hydrated lanthanide chlorides in absolute ethanol by an improved reported method. The complexes were identified as the general formula of RE(Et₂dtc)₃(phen) (RE=La, Pr, Nd, Sm) by chemical and elemental analyses. IR spectra of the complexes showed that the RE³⁺ was coordinated with sulfur atoms of NaEt₂dtc and nitrogen atoms of o-phen. The constant-volume combustion energies of complexes, Δ_cU, were determined by a precise rotating-bomb calorimeter at 298.15 K. The standard enthalpies of combustion, Δ_cH_m^?, and standard enthalpies of formation, Δ_fH_m^?, were calculated for these complexes, respectively.     

Determination of combustion energies and the standard enthalpies of formation for the complexes of RE(Et_2dtc)_3(phen)

Solid complexes, RE(Et2dtc)3(phen) (RE=La, Pr, Nd, Sm-Lu), were synthesized with sodium diethyldithiocarbamate (NaEt2dtc3H2O),1,10-phenanthroline (o-phen·H2O) and hydrated lanthanide chlorides in absolute ethanol. The constant-volume combustion energies of complexes,ΔcU, were determined by a precise rotating-bomb calorimeter at 298.15 K. The standard enthalpies of combustion,ΔcHmθ, and standard enthalpies of formation,ΔfHmθ, were calculated for these complexes, respectively. The experiment results showed the "tripartite effect" of rare earth.     

无水钾镁矾类复盐(A＋)2Cd2(SO4)3的热化学

The standard molar formation enthalpies of (A＋)2Cd2(SO4)3[A＋ is NH＋ 4 or K＋] are determined from the enthalpies of dissolution (ΔsHm) of [(A＋)2SO 4(s)＋2CdSO4(s)] and (A＋)2Cd2(SO4)3(s) in twice distilled water or 3 mol•L－1 HNO3 solvent respectively,at 298.2 K,as: ΔfHm [(NH4)2Cd2(SO4)3,s,298.2K]=－3031.74±0.08 kJ•mol－1 ΔfHm [K2Cd2(SO4)3,s,298.2K]=－3305.52±0.17 kJ•mol－1     

室温离子液体EMIES的标准生成焓

在(298.15 ±0.01) K下用转动弹热量计测定了离子液体硫酸乙酯-1-甲基-3-乙基咪唑(EMIES)及合成它的原料1-甲基咪唑的恒容燃烧热,通过计算得到它们的标准燃烧焓 分别为(－2671±2) 和(－286.3±0.5) kJ·mol－1;标准生成焓 分别为(－3060±3) kJ·mol－1和(－2145±4) kJ·mol－1.结合文献上硫酸二乙酯的标准生成焓数据,得到了合成离子液体EMIES的反应热(－102.3±1.0) kJ·mol－1,与合成实验中观察到的强烈放热现象是一致的.根据离子液体EMIES的热容数据,计算了不同温度下EMIES的标准生成焓.     

Determination of combustion energies and the standard enthalpies of formation for the complexes of RE(Et2dtc)3(phen)

Solid complexes, RE(Et₂dtc)₃(phen) (RE=La, Pr, Nd, Sm—Lu), were synthesized with sodium diethyldithiocarbamate (NaEt₂dtc3H₂O), 1,10-phenanthroline (o-phen•H₂O) and hydrated lanthanide chlorides in absolute ethanol. The constant-volume combustion energies of complexes, Δ _C U, were determined by a precise rotating-bomb calorimeter at 298.15 K. The standard enthalpies of combustion, Δ_CH_m ^θ, and standard enthalpies of formation, Δ_fH_m ^θ, were calculated for these complexes, respectively. The experiment results showed the “tripartite effect” of rare earth.

     

烟酸的低温热容和标准摩尔生成焓

利用精密自动绝热热量计测量了分析纯烟酸在78～400 K温区的低温热容. 用最小二乘法将实验摩尔热容对温度进行拟合, 得到了热容随温度变化的多项式方程. 用此方程进行数值积分, 得到在此温区每隔5 K的舒平热容值和相对于298.15 K时的热力学函数值. 利用精密静止氧弹燃烧热量计测定了烟酸在298.15 K时的恒体积燃烧能为 Δ_cU＝ －(24528.3±16.1) J•g^－1. 依据物质燃烧焓定义计算出烟酸的标准摩尔燃烧焓为: Δ_cH_m^o＝－(3019.05±1.98) kJ•mol^－1. 最后, 依据Hess定律计算出烟酸的标准摩尔生成焓为: Δ_fH_m^o＝－(56.76±2.13) kJ•mol^－1.