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1.
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.  相似文献   

2.
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, ΔcU, were determined by a precise rotating-bomb calorimeter at 298.15 K. The standard enthalpies of combustion, ΔcHm?, and standard enthalpies of formation, ΔfHm?, were calculated for these complexes, respectively.  相似文献   

3.
在无水乙醇中,用吡咯烷二硫代氨基甲酸铵(APDTC)和1,10-邻菲咯啉(o-phen·H2O)与TmCl3·3.65H2O作用,合成了未见文献报道的三元固态配合物,确定它的组成为Tm[(C5/sub>H8NS2)3(C12H8N2)]。 用RD496-Ⅲ微量热计测定了298.15 K下水合氯化铥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不同温度下标题化合物液相生成反应的焓变。在实验和计算基础上,得到了液相生成反应的热力学参数(活化焓、活化熵和活化自由能),速率常数和动力学参数(表现活化能、频率因子和反应级数)。通过合理的热化学循环,求得了298.15 K时标题化合物的固相生成反应焓变;推导了用该热量计测定固态物质比热容的计算式,并测定了题目配合物298.15 K的比热容。用RBC-Ⅱ精密转动弹热量计测定了题目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。  相似文献   

4.
合成了无水乳酸配合物(NH4)2[Sr(C3H5O3)4]。用X射线单晶衍射仪对该配合物的晶体结构进行了表征,确定了其组成、空间结构和配位方式。绘制了配合物的Hirshfeld表面和2D指纹图,揭示了分子间的相互作用以及该配合物具有多个配位位点和较强的配位活性。根据相关的晶体数据计算出了该配合物的晶格能及其对应阴离子的摩尔体积,计算得到该配合物的晶格能为2 742.9 kJ·mol-1。用等温环境反应-溶解量热计测量了该配合物在298 K超纯水溶剂中的溶解焓。根据Pitzer电解质溶液理论,在298 K下获得了该配合物的无限稀释摩尔溶解焓ΔsHm和Pitzer参数,确定该配合物的ΔsHm为(114.01±0.04) kJ·mol-1。计算了该配合物的表观相对摩尔焓(ΦL)以及不同浓度下溶质和溶剂的相对偏摩尔焓(L1L2)。最后,根据晶格能和ΔsHm设计了热化学循环,并计算出了阴离子的水合焓值。热重和微商热重曲线进一步揭示了该配合物的结构。  相似文献   

5.
在无水乙醇中, 使低水合氯化稀土 (RE = Ho, Er, Tm, Yb, Lu) 与吡咯烷二硫代氨基甲酸铵 (APDC)和1,10-菲咯啉 (o–phen•H2O) 反应, 制得其三元固态配合物. 用化学分析和元素分析确定它的组成为RE(C5H8NS2)3(C12H8N2) (RE = Ho, Er, Tm, Yb, Lu). IR光谱说明RE3+ 分别与3个PDC的6个硫原子双齿配位, 同时与o–phen的2个氮原子双齿配位, 配位数为8. 用精密转动弹热量计测定了它们的恒容燃烧热△cU分别为(-16788.46 ± 7.74), (-15434.53 ± 8.28), (-15287.80 ± 7.31), (-15200.50 ± 7.22)和(-15254.34 ± 6.61) kJ•mol-1; 并计算了它们的标准摩尔燃烧焓△cHmθ和标准摩尔生成焓△fHmθ分别为( -16803.95 ± 7.74), (-15450.02 ± 8.28), (-15303.29 ± 9.28), (-15215.99 ± 7.22), (-15269.83 ± 6.61) kJ • mol-1和 (-1115.42 ± 8.94), (-2477.80 ± 9.15), (-2619.95 ± 10.44), (-2670.17 ± 8.22), (-2650.06 ± 8.49) kJ•mol-1.  相似文献   

6.
合成了无水乳酸配合物(NH4)2[Sr(C3H5O3)4]。用X射线单晶衍射仪对该配合物的晶体结构进行了表征,确定了其组成、空间结构和配位方式。绘制了配合物的Hirshfeld表面和2D指纹图,揭示了分子间的相互作用以及该配合物具有多个配位位点和较强的配位活性。根据相关的晶体数据计算出了该配合物的晶格能及其对应阴离子的摩尔体积,计算得到该配合物的晶格能为2742.9 kJ·mol-1。用等温环境反应-溶解量热计测量了该配合物在298 K超纯水溶剂中的溶解焓。根据Pitzer电解质溶液理论,在298 K下获得了该配合物的无限稀释摩尔溶解焓△sHm和Pitzer参数,确定该配合物的△sHm为(114.01±0.04) kJ·mol-1。计算了该配合物的表观相对摩尔焓(ΦL)以及不同浓度下溶质和溶剂的相对偏摩尔焓(L1L2)。最后,根据晶格能和△sHm设计了热化学循环,并计算出了阴离子的水合焓值。热重和微商热重曲线进一步揭示了该配合物的结构。  相似文献   

7.
以高氯酸钐和缬氨酸为原料在蒸馏水中合成了一种稀土高氯酸盐-缬氨酸配合物[Sm2(L-α-Val)4(H2O)8](ClO4)6。利用TG/DTG、化学和元素分析、FTIR等技术表征了配合物的结构,确定其组成为:[Sm2(L-α-Val)4(H2O)8](ClO4)6。用精密绝热量热仪测量了它在78~371 K温区的热容,用最小二乘法将该温区的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,得到每隔5 K的舒平热容值和相对于298.15 K的热力学函数值。根据TG/DTG结果,推测了该配合物的热分解机理。另外,依据Hess定律,通过设计合理的热化学循环,利用等温环境溶解-反应热量计分别测量量热反应的反应物和产物在所选溶剂中的溶解焓,从而确定反应的反应焓为:ΔrHm?=(24.83±0.85) kJ·mol-1。最后,利用反应的反应焓和其它反应物和产物已知的热力学数据计算出配合物的标准摩尔生成焓为:-(8 010.01± 3.90) kJ·mol-1。  相似文献   

8.
在乙醇和水的混合溶剂中以间硝基苯甲酸(m-nitrobenzoic acid)、邻菲咯啉(phen)为原料合成了一个新的配合物[Cd(m-nitrobenzoic acid)2(phen)2]·(H2O)2,该配合物晶体属三斜晶系,空间群P1。配合物中镉原子与2个phen的4个N原子和2个间硝基苯甲酸根的3个羧基氧原子配位形成七配位的五角双锥结构。电化学性质研究表明:标题配合物  相似文献   

9.
稀土配合物[Nd(o-NO2-C6H4COO)3(DMF)2]2的合成及其晶体结构   总被引:2,自引:0,他引:2  
赵丽芳  陈亚芍 《化学学报》2007,65(8):667-672
合成了一种新的双核倒反中心的稀土钕配合物[Nd(o-NO2-C6H4COO)3(DMF)2]2. 通过元素分析, 核磁共振谱和红外光谱对配合物的组成和结构进行了表征, 用热重分析研究了该配合物的热稳定性, 用X射线单晶衍射法测定了其晶体的结构. 钕配合物[Nd(o- NO2-C6H4COO)3(DMF)2]2晶体属三斜晶系, 空间群P-1, 晶胞参数a=1.18652(12) nm, b=1.24784(13) nm, c=1.29958(13) nm, α=64.220 (1)°, β=66.306 (1)°, γ=71.825 (1)°, V=1.5645 (3) nm3, Dc=2.167 mg/m3, Z=2, μ=3.415 mm-1, F(000)=986. 配合物中每个Nd(Ш)被4个邻硝基苯甲酸根桥联, Nd(Ш)的配位数为8, 配位原子分别来自于5个邻硝基苯甲酸羧酸根的6个氧原子和2个DMF的羰基氧原子. 配合物中的氢键和ππ 堆积作用使其成为三维立体结构. 同时发现了标题配合物固体具有光致发光现象, 发光性能测试表明该配合物具有很好的荧光性质.  相似文献   

10.
[La(CH2ClCOO)2(NO3)(phen)(H2O)]n的合成和晶体结构   总被引:5,自引:0,他引:5  
合成了混合阴离子配合物[La(CH2ClCOO)2(NO3)(phen)(H2O)]n。配合物经元素分析、IR、DTA-TG和UV等表征。用X射线单晶结构分析解析了标题配合物的晶体结构,三斜,空间群P1,晶胞参数为a=10.533(2)?,b=13.136(3)?,c=7.776(1)?,α=96.59(1)°,β=95.76(1)°,γ=108.42(2)°,V=1003.3(3)?3,Z=2,Dc=1.940 g/cm3, F(000)=572, μ(Mo Kα)=24.36 cm-1。  相似文献   

11.
Yang  Xuwu  Zhu  Li  Chen  Sanping  Gao  Shengli  Shi  Qizhen 《中国科学:化学(英文版)》2005,48(1):88-92

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, ΔCHm θ, and standard enthalpies of formation, ΔfHm θ, were calculated for these complexes, respectively. The experiment results showed the “tripartite effect” of rare earth.

  相似文献   

12.
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, ΔCHm θ, and standard enthalpies of formation, ΔfHm θ, were calculated for these complexes, respectively. The experiment results showed the “tripartite effect” of rare earth.  相似文献   

13.
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.  相似文献   

14.
以铜试剂(NaEt2dtc•3H2O)和邻菲咯啉(o-phen•H2O) 与水合氯化铽(TbCl3•3.75H2O)在无水乙醇中制得了三元固态配合物.化学分析和元素分析确定其组成为Tb(Et2dtc)3(phen).IR光谱研究表明配合物中Tb3+与NaEt2dtc中的硫原子双齿配位,同时与phen的氮原子双齿配位.用Calvet微热量计测定了298.15 K下液相生成反应的焓变ΔrHmθ(l),为(-21.819±0.055) kJ•mol-1,通过热化学循环计算了固相生成反应焓变ΔrHmθ(s),为(128.476±0.675) kJ•mol-1.改变反应温度,研究了液相生成反应的热动力学.用精密转动弹热量计测得配合物的恒容燃烧能ΔcU为(-17646.95±8.64) kJ•mol-1,经计算其标准燃烧焓ΔcHHmθ和标准生成焓ΔfHmθ分别为(-17666.16±8.64) kJ•mol-1和(-1084.04±9.49) kJ•mol-1.  相似文献   

15.
A calculation formula for determining the specific heat capacity of solid compound with an improved RD496-Ⅲ microcalorimeter was derived. The calorimetric constant and precision determined by the Joule effect were (63.901±0.030)μV/mW and 0.3% at 298.15 K, respectively, and the total disequilibrium heat has been measured by the Peltier effect. The specific heat capacities of two standard substances (benchmark benzoic acid and α-Al2O3) were obtained with this microcalorimeter, and the differences between their calculated values and literature values were less than 0.4%. Similarly, the specific heat capacities of thirteen solid complexes, RE(Et2dtc)3(phen) (RE=La, Pr, Nd, Sm-Lu, Et2dtc: diethyldithiocarbamate ion, phen: 1,10-phenanthroline) were gained, and their total deviations were within 1.0%. These values were plotted against the atomic numbers of rare-earth, which presents tripartite effect, suggesting a certain amount of covalent character in the bond of RE^3+and ligands, according to Nephelauxetic effect of 4f electrons of rare earth ions.  相似文献   

16.
Introduction A series of lanthanide sulfide complexes have beenlargely used for ceramics and thin film materials1 andthese complexes could be prepared from the precursorswhich are the compounds containing lanthanide-sulfurbonds.2-4 For instance, the compounds synthesized with[(alkyl)2dtc]-, phen?H2O and lanthanide salts were usedas the volatile precursors for preparing lanthanide sul-fide, its friction properties in lubricant was investigatedin literature 5 and the preparation and propertie…  相似文献   

17.
采用均匀沉淀法,在20%的乙醇水溶液中,用水杨酸、维生素B3与稀土硝酸盐合成了一类新的稀土三元配合物.通过元素分析、化学分析、摩尔电导、红外光谱、紫外光谱、热重-微分热重分析等手段对配合物的结构和性质进行表征,确定了它们的组成通式为[RE(C7H5O3)2(C6H4NO2)·H2O](RE=La,Ce,Nd).维生素B3吡啶环上的N原子和水杨酸的酚羟基均未参与配位,两种配体均是脱质子后以羧酸根与RE3+离子配位,且成键以离子性为主,兼有部分共价性.在298.15 K,用精密的溶解-反应热量计分别测量了配位反应相关各物质的溶解焓,根据盖斯(Hess)定律求得合成反应的标准摩尔反应焓r mHФ分别为:(180.61±0.72)、(187.25±0.68)和(185.61±0.26)kJ/mol.进而求出配合物的标准摩尔生成焓为:f mHФ[La(C7H5O3)2(C6H4NO2)·H2O(s),298.15 K]=-(2493.9±2.9)、f mHФ[Ce(C7H5O3)2(C6H4NO2)·H2O(s),298.15 K]=-(2441.0±2.8)和f mHФ[Nd(C7H5O3)2(C6H4NO2)·H2O(s),298.15 K]=-(2463.1±2.9)kJ/mol.  相似文献   

18.
Thirteen solid ternary complexes Ln(Pdc)3(Phen) (Ln = La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu;) have been synthesized in absolute ethanol by rare-earth element chloride low hydrate reacting with the mixed ligands of ammonium pyrrolidinedithiocarbamate (APdc) and 1,10-phenanthroline · H2O (o-Phen · H2O) in the ordinary laboratory atmosphere without any cautions against moisture or air sensitivity. IR spectra of the complexes showed that the Ln3+ ion was coordinated with six sulfur atoms of three Pdc and two nitrogen atoms of o-Phen · H2O. It was assumed that the coordination number of Ln3+ is eight. The constant-volume combustion energies of the complexes, Δc U, were determined by a precise rotate-bomb calorimeter at 298.15 K. Their standard molar enthalpies of combustion, Δc H m o , and standard molar enthalpies of formation, Δf H m o were calculated. The text was submitted by the authors in English.  相似文献   

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