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1.
在无水乙醇中, 合成了组成为RE(C5H8NS2)3(C12H8N2) (RE=La, Pr, Nd, Sm~Lu) 的固态配合物. IR光谱表明配合物中稀土离子(RE3 )与吡咯烷二硫代氨基甲酸铵 (APDC)中的硫原子和1, 10-邻菲咯琳(o-phen) 中的氮原子均双齿配位; UV光谱显示配合物中o-phen与稀土离子之间的能量传递是主要过程, 配合物的最大吸收与o-phen相比有微小的红移; FS光谱表明配合物Sm(C5H8NS2)3(C12H8N2)和Eu(C5H8NS2)3(C12H8N2)具有很强的荧光性质. 相似文献
2.
A
solid complex Eu(C 5H 8NS 2) 3(C 12H 8N 2) has been obtained from reaction of
hydrous europium chloride with ammonium pyrrolidinedithiocarbamate (APDC)
and 1,10-phenanthroline ( o-phen⋅H 2O)
in absolute ethanol. IR spectrum of the complex indicated that Eu 3+
in the complex coordinated with sulfur atoms from the APDC and nitrogen atoms
from the o-phen. TG-DTG investigation provided
the evidence that the title complex was decomposed into EuS.
The
enthalpy change of the reaction of formation of the complex in ethanol, Δ r
H
m
θ( l), as –22.214±0.081 kJ mol –1,
and the molar heat capacity of the complex, c
m,
as 61.676±0.651 J mol –1 K –1,
at 298.15 K were determined by an RD-496 III type microcalorimeter. The enthalpy
change of the reaction of formation of the complex in solid, Δ r
H
m
θ( s), was calculated as 54.527±0.314 kJ mol –1
through a thermochemistry cycle. Based on the thermodynamics and kinetics
on the reaction of formation of the complex in ethanol at different temperatures,
fundamental parameters, including the activation enthalpy (Δ H
≠
θ),
the activation entropy (Δ S
≠
θ),
the activation free energy (Δ G
≠
θ),
the apparent reaction rate constant ( k),
the apparent activation energy ( E), the
pre-exponential constant ( A) and the reaction
order ( n), were obtained. The constant-volume
combustion energy of the complex, Δ c
U,
was determined as –16937.88±9.79 kJ mol –1
by an RBC-II type rotating-bomb calorimeter at 298.15 K. Its standard enthalpy
of combustion, Δ c
H
m
θ,
and standard enthalpy of formation, Δ f
H
m
θ,
were calculated to be –16953.37±9.79 and –1708.23±10.69
kJ mol –1, respectively. 相似文献
3.
在无水乙醇中,使低水合氯化稀土(RE=La, Pr, Nd, Sm)与吡咯烷二硫代氨基甲酸铵(APDC)和1,10-邻二氮菲(σ-phen·H 2O)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们的组成为RE (C 5H 8NS 2) 3(C 12H 8N 2) (RE= La, Pr, Nd, Sm).IR光谱说明RE 3+分别与3个PDC-的6个硫原子双齿配位,同时与σ-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Δ cU,分别为-17776.94±7.72, -17810.41±7.93, -17762.71±7.91和-17482.42±9.35 kJ·mol -1;并计算了它们的标准摩尔燃烧焓和标准摩尔生成焓,分别为-17792.43±7.72, -17825.90±7.93, -17778.20±7.91, -17497.91±9.35 kJ*mol -1和-83.05±8.60, -64.70±9.40, -104.77±8.78, -388.70±10.13 kJ·mol -1.估算出未研究的同类配合物Ce(C 5H 8NS 2) 3(C 12H 8N 2)和Pm(C 5H 8NS 2) 3(C 12H 8N 2)的和分别为-17815, -17660 kJ·mol -1和-60, -217 kJ·mol -1. 相似文献
4.
The enthalpy change of formation of the reaction of hydrous dysprosium chloride with ammonium pyrrolidinedithiocarbamate (APDC) and 1,10-phenanthroline (o-phen•H2O) in absolute ethanol at 298.15 K has been determined as (-16.12 ± 0.05) kJ•mol-1 by a microcalormeter. 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) kJ•molt-1 by a thermochemistry cycle. The values of the enthalpy change of formation both in liquid-phase and solid-phase reaction indicated that the complex could only be synthesized in liquid-phase reaction. 相似文献
5.
The enthalpy change of formation of the reaction of hydrous dysprosium chloride with ammonium pyrrolidinedithiocarbamate (APDC) and 1,10-phenanthroline (o-phen·H2O) in absolute ethanol at 298.15 K has been determined as (-16.12±0.05) kJ·mol-1 by a microcalor-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) kJ·mol-1 by a thermochemistry cycle. The values of the enthalpy change of formation both in liquid-phase and solid-phase reaction indicated that the complex could only be synthesized in liquid-phase reaction. 相似文献
6.
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)]. 相似文献
7.
The novel ternary solid complex Gd(C 5H 8NS 2) 3(C 12H 8N 2) has been obtained from the reaction of hydrous gadolinium chloride, ammonium pyrrolidinedithiocarbamate (APDC), and 1,10-phenanthroline
( o-phen · H 2O) in absolute ethanol. The complex was described by an elemental analysis, TG-DTG, and an IR spectrum. The enthalpy change
of the complex formation reaction from a solution of the reagents, Δ r
H
m
ϑ
(sol), and the molar heat capacity of the complex, c
m
, were determined as being − 15.174 ± 0.053 kJ/mol and 72.377 ± 0.636 J/(mol K) at 298.15 K by using an RD496-III heat conduction
microcalorimeter. The enthalpy change of a complex formation from the reaction of the reagents in a solid phase, Δ r
H
m
ϑ
(s), was calculated as being 52.703 ± 0.304 kJ/mol on the basis of an appropriate thermochemical cycle and other auxiliary
thermodynamic data. The thermodynamics of the formation reaction of the complex was investigated by the reaction in solution.
Fundamental parameters, the activation enthalpy (Δ H
≠
ϑ
), the activation entropy (Δ S
≠
ϑ
), the activation free energy (Δ G
≠
ϑ
), the apparent reaction rate constant ( k), the apparent activation energy ( E), the preexponential constant ( A), and the reaction order ( n), were obtained by the combination of the thermochemical data of the reaction and kinetic equations, with the data of thermokinetic
experiments. The constant-volume combustion energy of the complex, Δ c
U, was determined as being −17588.79 ± 8.62 kJ/mol by an RBC-II type rotatingbomb calorimeter at 298.15 K. Its standard enthalpy
of combustion, Δ c
H
m
ϑ
, and standard enthalpy of formation, Δ f
H
m
ϑ
, were calculated to be −17604.28 ± 8.62 and −282.43 ± 9.58 kJ/mol, respectively.
The text was submitted by the authors in English. 相似文献
8.
The novel branched chain-type nitridosilicates Ce 5Si 3N 9 and La 5Si 3N 9 have been synthesized in a radio-frequency furnace starting from the respective metals and silicon diimide Si(NH) 2 at 1625 °C for La 5Si 3N 9 and 1650 °C for Ce 5Si 3N 9, respectively. The structure of Ce 5Si 3N 9 has been determined by single-crystal X-ray diffraction (Ce 5Si 3N 9, Cmca (no. 64), a = 10.567(2) Å, b = 11.329(2) Å, c = 15.865(3) Å, V = 1899.3 Å 3, Z = 8, R1 = 0.0391, 1480 independent reflections, 90 refined parameters). The structure of isotypic La 5Si 3N 9 has been refined by the Rietveld method, starting from single-crystal data of Ce 5Si 3N 9 (La 5Si 3N 9, Cmca (no. 64), a = 10.647(4) Å, b = 11.414(4) Å, c = 16.030(5) Å, V = 1948.1 Å 3, Z = 8, RP = 0.0348, RF2 = 0.0533). Both compounds are built up of alternating Q 2- and Q 3-type corner sharing SiN 4 tetrahedra with additional corner sharing Q 1-units attached to the Q 3-tetrahedra pointing alternately in opposing directions. These zipper-like chains are intertwined in both directions perpendicular to the chain itself to form a three-dimensionally interlocked structure with the rare-earth ions situated between the chains. Magnetic measurements resulted in a ferromagnetic ground state with a magnetic moment in agreement with Ce 3+. 相似文献
9.
The luminescent characteristics of RE (RE 3+ = Eu, Tb, Dy, Sm and Tm)-doped K 2GdZr(PO 4) 3 have been investigated. The band in the range of 130–157 nm in the VUV excitation spectra of these compounds is attributed to the host lattice or PO 43? group absorption and the band from 157 nm to 215 nm with the maximum at 188 nm is due to the O–Zr charge transfer transition. For Eu 3+-doped sample, the relatively weak band of O 2?–Eu 3+ charge transfer (CTB) at 222 nm is observed and for Tb 3+-doped sample, the band at 223 nm is related to the 4f–5d spin-allowed transition of Tb 3+. For Dy 3+- and Sm 3+-doped samples, the O 2?–Dy 3+ and O 2?–Sm 3+ CTBs have not been observed, probably due to the 2p electrons of oxygen tightly bound to the zirconium ion in the host lattice. In Tm 3+-doped sample, the weak O 2?–Tm 3+ CTB is located at 170 nm. It is observed that there is energy transfer between the host and the luminescent activators (e.g. Eu 3+, Tb 3+ and Sm 3+) except for Tm 3+. 相似文献
10.
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YbCl3·3.84H2O作用, 合成了三元固态配合物, 确定它的组成为Yb[(C5H8NS2)3(C12H8N2)]. 用RD496-Ⅲ微量热计测定了298.15 K下水合氯化镱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; 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)和动力学参数(速率常数、表观活化能、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, 并测定了该配合物298.15 K的比热容. 相似文献
11.
The compounds (NC(12)H(8)(NH)(2))[Ln(N(3)C(12)H(8))(4)], Ln = Y, Tb, Yb, and [Ln(N(3)C(12)H(8))(2)(N(3)C(12)H(9))(2)][Ln(N(3)C(12)H(8))(4)](N(3)C(12)H(9))(2), with Ln = La, Sm, Eu, were obtained by reactions of the group 3 metals yttrium and lanthanum as well as the lanthanides europium, samarium, terbium, and ytterbium with 2-(2-pyridyl)-benzimidazole. The reactions were carried out in melts of the amine without any solvent and led to two new groups of homoleptic rare earth pyridylbenzimidazolates. The trivalent rare earth atoms have an eightfold nitrogen coordination of four chelating pyridylbenzimidazolates giving an ionic structure with either pyridylbenzimidazolium or [Ln(N(3)C(12)H(8))(2)(N(3)C(12)H(9))(2)](+) counterions. With Y, Eu, Sm, and Yb, single crystals were obtained whereas the La- and Tb-containing compounds were identified by powder methods. The products were investigated by X-ray single crystal or powder diffraction and MIR and far-IR spectroscopy, and with DTA/TG regarding their thermal behavior. They are another good proof of the value of solid-state reaction methods for the formation of homoleptic pnicogenides of the lanthanides. Despite their difference in the chemical formula, both types (NC(12)H(8)(NH)(2))[Ln(N(3)C(12)H(8))(4)], Ln = Y (1), Tb (2), Yb (3), and [Ln(N(3)C(12)H(8))(2)(N(3)C(12)H(9))(2)][Ln(N(3)C(12)H(8))(4)](N(3)C(12)H(9))(2), Ln = La (4), Sm (5), Eu (6), crystallize isotypic in the tetragonal space group I4(1). Crystal data for (1): T = 170(2) K, a = 1684.9(1) pm, c = 3735.0(3) pm, V = 10603.5(14) x 10(6) pm(3), R1 for F(o) > 4sigma(F(o)) = 0.053, wR2 = 0.113. Crystal data for (3): T = 170(2) K, a = 1683.03(7) pm, c = 3724.3(2) pm, V = 10549.4(14) x 10(6) pm(3), R1 for F(o) > 4sigma(F(o)) = 0.047, wR2 = 0.129. Crystal data for (5): T = 103(2) K, a = 1690.1(2) pm, c = 3759.5(4) pm, V = 10739(2) x 10(6) pm(3), R1 for F(o) > 4sigma(F(o)) = 0.050, wR2 = 0.117. Crystal data for (6): T = 170(2) K, a = 1685.89(9) pm, c = 3760.0(3) pm, V = 10686.9(11) x 10(6) pm(3), R1 for F(o) > 4sigma(F(o)) = 0.060, wR2 = 0.144. 相似文献
12.
在无水乙醇中, 用吡咯烷二硫代氨基甲酸铵(APDTC)和1,10-邻二氮菲(phen)与LaCl3·3.94H2O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La[(C5H8NS2)3(C12H8N2)]. X粉末衍射说明它为一新相化合物. IR光谱说明配合物中La3 分别与3个APDTC的6个硫原子双齿配位, 同时与phen的两个氮原子双齿配位, 配位数为8. TG-DTG分析显示其热分解为一步生成1/2La2S3 3C. 用微量热计测定了298.15 K下水合氯化镧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)和动力学参数(速率常数、表观活化能、频率因子和反应级数), 通过合理的热化学循环, 求得了标题化合物的固相反应焓变. 相似文献
14.
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•H 2O) 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(C 5H 8NS 2) 3(C 12H 8N 2) (RE = Ho, Er, Tm, Yb, Lu). IR光谱说明RE 3+ 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△ cH mθ和标准摩尔生成焓△ fH mθ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
15.
The thermal behavior of the complex Pr[(C5H8NS2)(C12H8N2)] in a dry nitrogen flow was examined by TG-DTG analysis. The TG-DTG investigations indicated that Pr[(C5H8NS2)(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 energyE was 115.89 kJ•mol−1 and the pre-exponential constant In[A/s] was 7.8697. The empirical kinetics model equation was proposed as\(f(\alpha ) = \frac{3}{2}(1 - \alpha )[ - 1n(1 - \alpha )]^{\frac{1}{3}} \). The X-ray powder diffraction patterns of the thermal decomposition products at 800 °C 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)(C12H8N2)]. 相似文献
16.
LaInO 3: Sm 3+, LaInO 3: Pr 3+ and LaInO 3: Tb 3+ phosphors were prepared through a Pechini-type sol–gel process. X-ray diffraction, field emission scanning electron microscopy, photoluminescence, and cathodoluminescence (CL) spectra were utilized to characterize the synthesized phosphors. XRD results reveal that the pure LaInO 3 phase can also be obtained at 700 °C. FE-SEM images indicate that the LaInO 3: Sm 3+, LaInO 3: Pr 3+ and LaInO 3: Tb 3+ phosphors are composed of aggregated spherical particles with sizes around 80–120 nm. Under the excitation of ultraviolet light and low voltage electron beams (1–5 kV), the LaInO 3: Sm 3+, LaInO 3: Pr 3+ and LaInO 3: Tb 3+ phosphors show the characteristic emissions of Sm 3+ ( 4G 5/2– 6H 5/2,7/2,9/2 transitions, yellow), Pr 3+ ( 3P 0– 3H 4, 3P 1– 3H 5, 1D 2– 3H 4 and 3P 0– 3F 2 transitions, blue–green) and Tb 3+ ( 5D 4– 7F 6,5,4,3 transitions, green) respectively. The corresponding luminescence mechanisms are discussed. These phosphors have potential applications in field emission displays. 相似文献
17.
The magnetic data of RE 2MnGe 6 (RE = La, Ce) and YMn 0.3Ge 2 are reported. La 2MnGe 6 and Ce 2MnGe 6 crystallize in the orthorhombic Ce 2CuGe 6 structure type, space group Amm2 (No. 38). The non-stoichiometric YMn 0.3Ge 2 compound crystallizes with the orthorhombic CeNiSi 2-type structure (space group Cmcm (No. 36)). The studied RE 2MnGe 6 (RE = La, Ce) intermetallics are characterized by ferromagnetic properties with Curie temperatures 177 (La) and 150 K (Ce), respectively. For YMn 0.3Ge 2 the low-field magnetic measurements indicate the antiferromagnetic property below 395 K with the small ferromagnetic component. The values of the magnetic moments in the ordered state indicate the ferromagnetic ordering in La 2MnGe 6 and complex magnetic order with the ferromagnetic component in YMn 0.3Ge 2 and Ce 2MnGe 6. The hysteresis loop and values of the coercivity field indicate that these compounds are soft magnetic materials. 相似文献
18.
Conclusions For B 10H 12L 2, where L=NH 3, C 5H 5N, or C 9H 7N, features of thermal transformations in the range 25–850°C and the composition of the pyrolysis products are determined. The latter are x-ray amorphous phases, containing nitride, carbide, boron carbide, boron, and carbon.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2481–2484, November, 1988. 相似文献
19.
Summary Two novel charge-transfer (CT) heteropoly complexes, (C 8H 12N 2) 5H 7PMo 12O 40
(1) and (C 8H 12N 2) 3H 3-PMo 12O 40·5H 2O (2), prepared by reacting p-Me 2NC 6H 4NH 2 with the four-electron heteropoly blue H 7PMo 12O 40·12H 2O and heteropoly acid H 3PMo 12O 40· xH 2O, respectively, were characterized by elemental analysis, and u.v., i.r., XPS and e.s.r. spectroscopies. A sizable electron-transfer
interaction occurs within the product molecules and the heteropoly anions retain their Keggin structure. Their third-order
optical non-linearity coefficients were measured using the Z-scan technique at a concentration of 4.68 × 10 −6 mol dm −3 for (1) and 2.79 × 10 −6 mol dm −3 for (2), with I
0 = 2.38 × 10 13 w m −2 and λ = 532nm. The |χ (3)| for (1) is 2.61 × 10 −10 esu and |χ (3)| for (2) is 1.05 × 10 −10 esu. 相似文献
20.
The bimetallic ferromagnetic chain {[K(18-crown-6)][Mn(bpy)Cr(ox) 3]} ∞ ( 1) has been synthesized and characterized. It crystallizes in the orthorhombic chiral space group P2 12 12 1 [ a = 9.0510(2) Å, b = 14.4710(3) Å, c = 26.8660(8) Å, V = 3510.97(1) Å 3, Z = 2]. Compound 1 is made up by anionic [Mn(bpy)Cr(ox) 3] − 1D chains and cationic [K(18-crown-6)] + complexes. The magnetic exchange within the chain is ferromagnetic [ J = +7.8(7) cm −1]. In the solid state, the ferromagnetic chains are well isolated magnetically and no long range magnetic ordering has been observed above 2 K. 相似文献
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