稀土元素异硫氰酸盐水合物,RE(NCS)_3·nH_2O的低温热容和热力学性质的研究——Ⅰ.La(NCS)_3·7H_2O和Ce(NCS)_3·7H_2O

本文用全自动绝热量热计从13到300K测定了两种稀土元素异硫氰酸盐七水合物,La(NCS)_3·7H_2O和Ce(NCS)_3·7H_2O的热容。较详细描述了量热计结构和操作。在实验温区对两种化合物均未观察到明显的热异常现象。根据实验热容数据,用最小二乘拟合方法得到了计算这两种化合物13—300K热容值的多项式方程。13K以下的热容值用Debye和Einstein热容函数进行了估算。计算出了O—300K的标准热力学函数,标准生成Gibbs能也被计算出来。     

LOW-TEMPERATURE HEAT CAPACITY AND THERMODYNAMIC FUNCTIONS OF 2-CHLORO-6-(TRICHLOROMETHYL)PYRIDINE

The heat capacity of 2- chloro- 6- (trichloromethyl)pyridine has heen measured with anadiabatic calorimeter in the range from 13 to 316K. There is no indication of any phasetransition or thermal anomaly in this temperature region for the present compound. Theresults have been compared with those reported in [1] in the overlapping temperaturerange. The experimental heat capacity data have been fitted to a smoothed curve by the aidof the effective frequency distribution method, and the heat capacities below 13K have beenobtained by extrapolating the fitting curve down to 0K. The standard molar thermodynamicfunctions between 0 and 400 K have been derived by combining the present heat capacitymeasurements with the previous ones. The values of C_p~o (T), S~o(T) - S~o(0), [H~o(T) -H~o(0)]/T, and - [G~o(T) - H~o(0)]/T at T = 298.15 K are 189.35, 244.60, 112 .45 and 132.15J·K~(-1)·mol~(-1), respectively.     

稀土元素异硫氰酸盐水合物的低温热容和热力学性质研究——Ⅲ.Sm(NCS)_3·6H_2O,Gd(NCS)_3·6H_2O,Yb(NCS)_3·6H_2O和Y(NCS)_3·6H_2O

用全自动绝热量热计测定了4种稀土异硫氰酸盐六水合物,Sm(NCS)_3·6H_2O,Gd(NCS)_3·6H_2O,Yb(NCS)_3·6H_2O和Y(NCS)_3·6H_2O在13～300 K间的热容,在实验温区上述化合物均未发现反常热容.根据实验热容数据用最小二乘拟合方法得出了计算这4种化合物在13～300 K温区内的热容多项式方程.13K以下的热容用 Debye-Einstein热容函数估算而得.计算了这些化合物在0～300 K间的标准热力学函数及其标准生成Gibbs能.     

Low-temperature heat capacities and thermodynamic properties of rare-earth triisothiocyanate hydrates (Ⅲ)——Sm(NCS)_3·6H_2O,Gd(NCS)_3·6H_2O,Yb(NCS)_3·6H_2O and Y(NCS)_3·6H_2O

The heat capacities of four RE isothiocyanate hydrates,Sm( NCS)3 6H2O,Gd( NCS)3 6H2O,Yb(NCS)3 6H2O and Y( NCS)3 6H2O,have been measured from 13 to 300 K with a fully-automated adiabatic calorimeter No obvious thermal anomaly was observed for the above-mentioned compounds in the experimental tem-peiatnre ranges.The polynomial equations for calculating the heat capacities of the four compounds in the range of 13-300K were obtained by the least-squares fitting based on the experimental Cp data.The Cp values below 13 K were estimated by using the Debye-Einstem heat capacity functions.The standard molar thermodynamic functions were calculated from 0 to 300 K.Gibbs energies of formation were also calculated.     

SYNTHESIS, STRUCTURE AND PROPERTIES OF Na_3[V_2O_3(nta)_2]·5H_2O

<正> Compound Na3 [V2O3 (nta )2 ]·5H2O (1) (ntaH3 = N (CH2CO2H)3) has been prepared by reduction of a mixture of (NH4)2[VO(O2)2Cl] and H3(nta) in H2O with Na2S2O4. The compound crystallizes in the triclinic system, space group P1 with Mr = 685. 2, a = 11. 050(6), b=12. 179(4), c=9. 792 (3)A,α=111.71(2),β= 98. 23(3), γ= 89. 36(2)°, Z=2, V = 1210. 5A3,λ(MoKa) = 0. 71069 A, F(000) = 694 and DC = 1. 880g/cm3. The structure was solved by direct methods and refined by full-matrix least squares to final R and Rw values of 0. 055 and 0. 065, respectively.The structure of the anion can be considered as two [VO(nta)] fragments connected by one μ2-O atom. Each vanadium atom in the fragment is coordinated by one vanadyl oxygen atom, one bridging-oxygen atom, three oxygen atoms and one nitrogen atom from (nta) ligand in a distorted octahedral geometry. In this paper, we have studied the conversion of compound 1 to mononuclear compound Na2[VO(O2) (nta)]·5H2O (2) by oxidation with hydrogen peroxide, as well as thei     

TRINUCLEAR BASIC CARBOXYLATE COMPOUNDS OF TRANSITION METALS PART 2. SYNTHESIS AND CRYSTAL STRUCTURE OF [Fe_3O (EtCO_2)_3(MeCO_2)_3(H_2O)_3]NO3·H_2O

<正> The title complex crystallizes in monoclinic system,space group C 2/m with α=19. 870(5),b=13. 070(2),c=18. 246(4)A ,β=134. 32(1)°,Mr = 707. 88, V=3390. 0A3.Z = 4,DC=1. 387g/cm3,F(000) = 1468,final R=0. 066 for 2244 independent reflections with Ⅰ >3σ(Ⅰ). The cation was shown to contain three Fe (Ⅲ) atoms at the apices of an equilateral triangle with a 3-O bridge.The Fe (1)-(μ3-O)and Fe(2)-(μ3-O) distances are 1. 907(6) and 1. 87(1) A , respectively. And mixed ligands of acetato and propionyloxy lato are bridged to each pair of the Fe(Ⅲ) atoms.     

PREPARATION AND CRYSTAL STRUCTURES OF Ln_2(S0_4)_3(H_2O)_4 (Ln=La COMPOUND Ⅰ;Nd,COMPOUND Ⅱ)

<正> The title crystal structures have been determined by X-ray diffraction. They crystallize in the monoclinic, space group P21/n, Z=4 with diaensions a= 12.388(1), b= 7.140(1), c= 14.302(1) A,β=90.65(1)° for compound Ⅰ, and a=12.987(2), b= 7.190(1), c=13.284(2) A,β=92.40(2)° for compound Ⅱ. The structures were solved by direct methods, and refined by full matrix least-squares to consistence factors R=0.026 for Ⅰ and R=0.031 for Ⅱ.     

CRYSTAL AND MOLECULAR STRUCTURE OF A DIPHENYL SULFOXIDE COMPLEX WITH CERIUM NITRATE, Ce(N0_3)_3[(C_6H_5)_2SO]_4

<正> The title complex crystallises in the triclinic, space group PT with two formula units in a unit cell of dimensions a=11.182(4), b=14.357(5), c=17.362(6) A and α= 84.08(3)°, β=72.79(3)°, r= 69.27(2)°, Dx=1.51 g.cm-3, V=2489.6(15) A3. The final index for 6319 observed reflections is 0.0274. The Ce3+ ion is coordinated by ten oxygen atoms with Ce-O distances varying from 2.469 to 2.706 A. The three nitrate groups are all bidentate ligands.     

THE SYNTHESIS AND CRYSTAL STRUCTURE OF NdBr_3(i-C_3H_7OH)_2(THF)_2

ＴＨＥ　ＳＹＮＴＨＥＳＩＳ　ＡＮＤ　ＣＲＹＳＴＡＬ　ＳＴＲＵＣＴＵＲＥ　ＯＦ　ＮｄＢｒ＿３（ｉ－Ｃ＿３Ｈ＿７ＯＨ）＿２（ＴＨＦ）＿２￥ＨｏｎｇＹｅＳＵＮ；ＣｈｕｎＨｕｉＨＵＡＮＧａｎｄＧｕａｎｇＸｉａｎＸＵ（ＲｅｓｅａｒｃｈＣｅｎｔｅｒｏｆＲａｒｅＥ...     

SYNTHESIS AND STRUCTURE OF Ni_2(PBu_3~n)_2(SC_7H_6S)_2

<正> The nickel(Ⅱ) complex Ni2(PBu3n)2(tdt)2(tdt = SC7H6S2-) containing dithiolato and phosphino ligands has been prepared and characterized by X-ray diffraction. The complex crystallizes in triclinic system, space group P1, with a = 14. 423(4), b = 15. 053(3), c=10. 648(3)(?), α=93.,95(2), β=100. 31(3), γ = 84. 16(2)°; V =2259.6 (?)3; Z = 2, Dc= 1. 22 gem-3, Mr = 830. 57; μ = 11. 076cm-1, F (000) = 888. In the complex, the Nickel atoms are linked by two bridging sulfur atoms from the two tdt ligands with the Ni-Ni distance of 2. 679 (?) . and each nickel atom is four coordinated by one phosphorus and three sulfur atoms with a square-planar geometry, the average length of Ni -S bond is 2. 193(?) and that of Ni-P bond 2.186(?).     

CRYSTAL STRUCTURE OF [Sm(CCl_3COO)_3(H_2O)_2]·2H_2O

<正> Biaqua-trichloroacetate-samarium dihydrate, [Sm(CCl3COO)3(H2O)2]-2H2O, Mr=707.54, orthorhombic, space group Pnne, with a = 19.158(5), b = 22.176(4), c= 9.798(4)A, Z= 8, V= 4162.7A3.F{000)= 2696,λ(MoKα)=0.71069A, Dx = 2.258 g/cm3, final R=0.061. The title compound has non-molecular structural character, and its structural units Sm(μ-CCl3COO)s/2-(H2O>2 constitute 2-dinensional infinite chains of Sm(μ-CCl3COO)4Sm(μ-CCl3-COO)2Sm.The Sa(Ⅲ) atom in each unit is bound to two O atoms from aqua-molecules and six 0 atoms from six bridging CCl3COO groups (four of which are shared with the SB atom of another unit, two shared with the Sm atom of a third unit) forming a square antiprism.     

Low temperature heat capacities and thermodynamic properties of rare earth triisothiocyanate hydrates——Pr(NCS)_3· 7H_2O and Nd(NCS)_3· 7H_2O

Heat capacities of Pr(NCS)3·7H2O and Nd(NCS)3· 7H2O haw been measured from 13 to 300 K by using a fully automated adiabatic calorimeter. Schottky anomaly was observed for Pr(NCS)3·7H2O below 50 K. The polynomial equations for calculating the heat capacity values of the two compounds in the range of 13-300 K were obtained by the least-squares fitting based on the experimental Cp data. The Cp values below 13 K were estimated by using the Debye-Einstein and Schottky heat capacity functions. The standard molar thermodynamic functions were computed from 0 to 300 K. The standard entropies and Gibbs energies of formation of the two compounds were also calculated.     

SYNTHESES AND SPECTROSCOPIC PROPERTIES OF LANTHANIDE COMPLEXES, Ln(acac)_3(Ph_3PO)_3

A series of new complexes of formula Ln(acac)_s(Ph_3PO)_3 (where Ln~(3+)=Nd~(3+), Sm~(3+), Eu~(3+), Tb~(3+), Ho~(3+)) have been prepared and characterized. The coordination of two ligands with lanthanide ions are studied by IR spectra, ~1H, ~(13)C, ~(31)P-NMR and metal-ligand charge tranafer tranaition is also discussed via electronic adaorption and luminescence spectroscopy.     

CRYSTAL AND MOLECULAR STRUCTURE OF TETRAAQUA TRIM TRATO SAMARIUM(Ⅲ) DIHYDRATE [Sm(H_2O)_4(NO3)_3] ·2H_2O

<正> [Sm(H2O)4(NO3)3]·2H2O,Mr=444. 46,triclinic,space group P1 ,a = 6.747(1),b=9. 156(1),c=11.673(l) A ,α= 69. 90(1),β=88. 88(1),γ=69. 29 (1)°,V = 629.0A3,Z=2,λ(MoKa) = 0. 7107A,F(000) = 430,Dx=2. 346/cm3,final R=0. 032. The Sm atom in the title complex has bicapped square antiprismtic coordination of oxygen atoms from four water molecules and three NO3 groups. The Sm -O(nitrato) and Sm-O(aqua) distances are in the ranges of 2. 517-2. 716 and 2. 407-2. 432A , respectively. The N-O bond lengths vary between 1. 209 and 1. 265 A with the shortest distances being those involving noncoordinated oxygen atoms. The two lattice water molecules are outside the coordination sphere of the Sm atom but participate in the network of intermolecular hydrogen bonds.     

Syntheses and Crystal Structures of Two Cyano-bridged Bimetallic Complexes [Ce(DMSO)_4(H_2O)_3Fe(CN)_6]·H_2O and [La(DMSO)_4(H_2O)_3Co(CN)_6]·H_2O(DMSO = Dimethylsulfoxide)

1INTRODUCTION Recently,cyano-bridged lanthanide-transition me-tal complexes have been extensively investigateddue to their potential applications as precursors in the preparation of rare earth orthoferrites,fluores-cent and magnetic materials[1].Various complexes of this system have been obtained in order to ex-plore the relations between structures and pro-perties by using different ligands,such as DMF,4,4?-bipy,and so on,to fill the coordination sites of lanthanide ions[2～9].But up to…     

THE STRUCTURAL CHEMISTRY OF PRASEODYMIUM COMPLEXES OF AMINO ACIDS I. THE CRYSTAL STRUCTURE OF COMPLEX {[Pr(Gly)_3(H_2O)_2]_2(ClO_4)_65H_2O

<正> Introduction. The title compound has been synthesized and its crystal struture determined by X-ray analysis. The crystal structure of this type of complex was reported for the first time, as far as we know.     

CRYSTAL AND MOLECULAR STRUCTURE OF [Cu_2(α-C_(10)H_7-CH_2CO_2)_4(DMF)_2](DMF)_2· H_2O

<正> The title complex crystallizes in the triclinic system, space group P1, a =11. 912(4), b = 13. 626(2), c=10. 040(3)(?), a=95. 03(2) ,β= 114. 8 (3), γ = 73. 58(3)°, V = 1418.0(?)3, Z = 1, D,= 1. 37g/cm3, F(000) = 612, R = 0. 064 for 4860 independent reflections [I>3σ(I)]. Each Cu atom is coordinated by the oxygen atoms from the C10H7CH2COO groups and DMF in a square pyramid geometry.     

CRYSTAL AND MOLECULAR STRUCTURE OF K(C_3H_(12)N_2)_2(HV_(10)O_(28_).8.5H_2O

<正> Preliminary information. Vanadium compounds plays an important role in catalysis since they have a property of easily changeable oxidation states. As a part of our study on vanadium compounds, the crystal structure of the title compound is reported, which is prepared by the reaction of (C_3H_(12)N_2)_2-V_2O_7, NaVO_3 with KOH in an aqueous solution.     

Synthesis, Crystal Structure and Spectral Properties of [Ce(NO_3)_5(H_2O)_2]·2(Hphen)·(H_2O)

1 INTRODUCTION Recently, the ternary or quaternary mixed anion complexes of cerium(III) containing 1,10-phenanthroline (phen) have attracted considerable attention due to their rich structural chemistry and appealing magnetic properties[1]. Panagiotopou…     

CRYSTAL STRUCTURE OF [Eu(μ-CH_3COC-O)(CH3COO)_2(H_2O)_2]_2·4H_2O

<正> C12H34O20Eu2,Mr=802.30 triclinic, space group P1, a= 8.955(2), b=9.328(1), c=10.536(2) A,α= 91.74(2),β=113.87(2),γ=118.23(2), V=681.7(2)A,Dm(flotation in CC14/ BrCH2CH2Br)=1.95,DX(Z=1) =1.954g cm-3,λ(MoKα)=0.71069 A,μ=6.41 cm-1,F(OOO)=391.92, T =. 295°K,final RF= 0.032 for 7483 observed reflections with |F0|>3a(|Fo|). The compound is isostructural with the known erbium complex,the basic unit being a centrosymmetric dimer composed of two nine-coordinate polyhedra sharing a common edge. An O atom in one or the three bidentate acetato groups about each europium atom serves as a bridge between the metal centars. The dimeric units are linked by hydrogen bonds involving both ligand and lattice water molecules to form a three-dimensional network.