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1.
A new synthesis of trisfluoroacetylactone (TFA) and hexafluoroacetylactone (HFA) Nd complexes: Nd(TFA)3 · 2H2O and Hd(HFA)3 · 2H2O is reported. The photoacoustic (PA) spectra in the 300–800 nm region of the compounds NdCl3 · 6H2O, Nd(TFA)3 · 2H2O and Nd(HFA)3 · 2H2O are reported. The PA absorption bands are assigned and their relative intensities represented by intensity branching vectors are calculated. The perturbation of the ligand on the energy levels of Nd3+ ion is discussed and a model of the relaxation process of Nd(HFA)3 · 2H2O is proposed based on its PA and absorption spectra.  相似文献   

2.
Fourier transform infrared reflection spectroscopy (incidence angle of 5°) was used to characterize thin films of dimethyl ether (DME) and of mixtures containing water and DME between 10 and 160 K under a pressure of 10−7 mbar. Solid DME has two solid phases: an amorphous phase which is obtained below 65 K and a crystalline phase >65 K. From 90 K, DME begins to sublimate with surface binding energy of 20±2 kJ mol−1. Vibrational spectrum of DME trapped in water ice remains nearly unchanged from 30 to 120 K. Between 120 and 130 K, a large part of DME is released and strong changes in the frequencies and the profile of the absorptions of DME are observed. This behavior suggests the formation of clathrate hydrate. Below 120 K, the trapped DME is hydrogen-bonded to water molecules.  相似文献   

3.
本文利用水热合成方法,将稀土氧化物与邻苯二乙酸(H2pda)反应得到了2个新颖的稀土配位聚合物{[Ln2(pda)3(H2O)2]·2H2O}n(Ln=Nd(1),La(2))。测定了它们的晶体结构,并进行了X-射线单晶衍射、红外光谱、荧光光谱和热重分析等性质的表征。晶体结构测定表明这2个化合物为异质同晶化合物。属单斜晶系,C2/c空间群。晶体学参数分别为配合物1:a=2.629 06(18)nm,b=1.611 72(11)nm,c=0.783 27(5)nm,β=93.173(5)°,V=3.313 9(4)nm3,Z=4,F(000)=1 840,μ=3.173 mm-1,Dc=1.878 g·cm-3,R1=0.022 6,wR2=0.060 9;配合物2:a=2.627 1(14)nm,b=1.614 9(8)nm,c=0.796 6(4)nm,β=92.850(9)°,V=3.375(3)nm3,Z=4,F(000)=1 816,μ=2.570 mm-1,Dc=1.823 g·cm-3,R1=0.0466,wR2=0.1416。化合物中邻苯二乙酸配体连接相邻的稀土金属离子,形成复杂的具有stp拓朴构型的三维网络结构。  相似文献   

4.
The compound [PbPh2(NO3)2(H2O)2] was synthesized and characterized by spectroscopic methods (IR; 1H, 13C and 207Pb NMR) and mass spectrometry. An X-ray diffraction study showed that the crystal is a supramolecular tridimensional network of hydrogen-bonded PbPh2(NO3)2(H2O)2 units in which the Pb atom is octacoordinated and adopts a distorted hexagonal bipyramidal geometry, with four O (bidentate nitrate) and two O (water) atoms in equatorial positions and two C-phenyl atoms in axial positions. The crystal of [PbMe3(NO3)(H2O)], obtained as a byproduct in the synthesis of PbMe2(NO3)2, contains chains of hydrogen-bonded PbMe3(NO3)(H2O) units in which the Pb atom is pentacoordinated with a slightly distorted trigonal bipyramidal environment. In this arrangement the three C-methyl atoms are equatorial and the O atoms from the monodentate nitrate and the water molecule are axial.  相似文献   

5.
本文首次报道三元体系Cu(NO3)2-CO(NH2)2-H2O(30℃)和La(NO3)3-CO(NH2)2-H2O(25℃)的等温溶度及饱和溶液、折光率,绘制相应的溶度图及折光率-组成图。体系中发现有组成为Cu(NO3)2·4CO(NH相似文献   

6.
《Thermochimica Acta》2001,370(1-2):65-71
The two-stage melting process and the thermal decomposition of [Ni(H2O)6](NO3)2 was studied by DSC, DTA and TG. The first melting point at 328 K is connected with the small and the second melting point at 362 K with the large enthalpy and entropy changes. The thermal dehydration process starts just above ca. 315 K and continues up to ca. 500 K. It consists of three well-separated stages, but the sample mass loss at each stage depends on the experimental regime. However, irrespective of the chosen regime, the total of registered mass losses in stage one and two amounts to three H2O molecules per one [Ni(H2O)6](NO3)2 molecule. The remaining three H2O molecules are gradually freed in the temperature range of 440–500 K in the third stage of the dehydration. Above 580 K, anhydrous Ni(NO3)2 decomposes into NO and NiO. The gaseous products were identified by quadrupole mass spectrometer (QMS), and the solid product was identified by X-ray diffraction (XRD) analysis.  相似文献   

7.
本文利用水热合成方法,将稀土氧化物与邻苯二乙酸(H2pda)反应得到了2个新颖的稀土配位聚合物{[Ln2(pda)3(H2O)2]·2H2O}n(Ln=Nd(1),La(2))。测定了它们的晶体结构,并进行了X-射线单晶衍射、红外光谱、荧光光谱和热重分析等性质的表征。晶体结构测定表明这2个化合物为异质同晶化合物。属单斜晶系,C2/c空间群。晶体学参数分别为配合物1a=2.62906(18)nm,b=1.61172(11)nm,c=0.78327(5)nm,β=93.173(5)°,V=3.3139(4)nm3,Z=4,F(000)=1840,μ=3.173mm-1,Dc=1.878g·cm-3,R1=0.0226,wR2=0.0609;配合物2a=2.6271(14)nm,b=1.6149(8)nm,c=0.7966(4)nm,β=92.850(9),V=3.375(3)nm3,Z=4,F(000)=1816,μ=2.570mm-1,Dc=1.823g·cm-3,R1=0.0466,wR2=0.1416。化合物中邻苯二乙酸配体连接相邻的稀土金属离子,形成复杂的具有stp拓朴构型的三维网络结构。  相似文献   

8.
A cobalt phosphonate (H3O)6·[Co4(H2O)4(HPMIDA)2(PMIDA)2)]·2H2O, 1, has been synthesized from a mild solvothermal reaction of Co(II) ion with N-(phosphonomethyl)iminodiacetic acid (H4PMIDA). Compound 1 crystallizes in the triclinic space group with cell parameters of , , , α=93.06(3)°, β=99.66(3)°, γ=90.34(3)° and Z=1. Compound 1 shows a novel tetra-nuclear molecular structure. In the crystal lattice, molecules of 1 hydrogen bond to each other to form two-dimensional (2D) layers, which are further linked together by the co-crystallized H2O molecules and H3O+ counter ions through hydrogen bonding to form the 3D supramolecular network. Thermogravimetric analysis, IR spectrum, magnetic susceptibility and luminescent spectra are given.  相似文献   

9.
Three new hydrated scandium selenites have been hydrothermally synthesized as single crystals and structurally and physically characterized. Sc2(SeO3)3·H2O crystallizes as a new structure type containing novel ScO7 pentagonal bipyramidal and ScO6+1 capped octahedral coordination polyhedra. Sc2(SeO3)3·3H2O contains typical ScO6 octahedra and is isostructural with its M2(SeO3)3·3H2O (M=Al, Cr, Fe, Ga) congeners. CsSc3(SeO3)4(HSeO3)2·2H2O contains near-regular ScO6 octahedra and has essentially the same structure as its indium-containing analogue. All three phases contain the expected pyramidal [SeO3]2- selenite groups. Crystal data: Sc2(SeO3)3·3H2O, Mr=524.85, trigonal, R3c (No. 161), , , , Z=6, R(F)=0.018, wR(F2)=0.036; Sc2(SeO3)3·H2O, Mr=488.82, orthorhombic, P212121 (No. 19), , , , , Z=4, R(F)=0.051, wR(F2)=0.086; CsSc3(SeO3)4(HSeO3)2·2H2O, Mr=1067.60, orthorhombic, Pnma (No. 62), , , , , Z=4, R(F)=0.035, wR(F2)=0.070.  相似文献   

10.
The syntheses and structural determination of NdIII and ErIII complexes with nitrilotriacetic acid (nta) were reported in this paper. Their crystal and molecular structures and compositions were determined by single-crystal X-ray structure analyses and elemental analyses, respectively. The crystal of K3[NdIII(nta)2(H2O)]·6H2O complex belongs to monoclinic crystal system and C2/c space group. The crystal data are as follows: a=1.5490(11) nm, b=1.3028(9) nm, c=2.6237(18) nm, β=96.803(10)°, V=5.257(6) nm3, Z=8, M=763.89, Dc=1.930 g cm−3, μ=2.535 mm−1 and F(000)=3048. The final R1 and wR1 are 0.0390 and 0.0703 for 4501 (I>2σ(I)) unique reflections, R2 and wR2 are 0.0758 and 0.0783 for all 10474 reflections, respectively. The NdIIIN2O7 part in the [NdIII(nta)2(H2O)]3− complex anion has a pseudo-monocapped square antiprismatic nine-coordinate structure in which the eight coordinate atoms (two N and six O) are from the two nta ligands and a water molecule coordinate to the central NdIII ion directly. The crystal of the K3[ErIII(nta)2(H2O)]·5H2O complex also belongs to monoclinic crystal system and C2/c space group. The crystal data are as follows: a=1.5343(5) nm, b=1.2880(4) nm, c=2.6154(8) nm, b=96.033(5)°, V=5.140(3) nm3, Z=8, M=768.89, Dc=1.987 g cm−3, μ=3.833 mm−1 and F(000)=3032. The final R1 and wR1 are 0.0321 and 0.0671 for 4445 (I>2σ(I)) unique reflections, R2 and wR2 are 0.0432 and 0.0699 for all 10207 reflections, respectively. The ErIIIN2O7 part in the [ErIII(nta)2(H2O)]3− complex anion has the same structure as NdIIIN2O7 part in which the eight coordinate atoms (two N and six O) are from the two nta ligands and a water molecule coordinate to the central NdIII ion directly.  相似文献   

11.
The rare-earth dicarboxylate hybrid materials [Ce(H2O)]2[O2C(CH2)2CO2]3 ([Ce(Suc)]) and [Sm(H2O)]2[O2C(CH2)2CO2]3·H2O ([Sm(Suc)]) have been hydrothermally synthesized (200°C, 3 days) under autogenus pressure. [Ce(Suc)] is triclinic, a=7.961 (3) Å, b=8.176 (5) Å, c=14.32 (2) Å, α=97.07° (7), β=96.75° (8), γ=103.73° (6), and z=2. The crystal structure of this compound has been determined using 3120 unique single crystal data. The final refinements let the agreement factors R1 and wR2(F2) converge to 0.0138 and 0.0363, respectively. [Ce(Suc)] is built up from infinite chains of edge-sharing nine-fold coordinated cerium atoms running along [100]. These chains are interconnected by the carbon atoms of the succinate anions, leading to a three-dimensional hybrid framework. The cell constants of [Sm(Suc)], isotypic with monoclinic C2/c [Pr(H2O)]2[O2C(CH2)2CO2]3·H2O ([Pr(Suc)]), were refined starting from X-ray powder data: a=20.275 (3) Å, b=7.919 (6) Å, c=14.130 (3) Å, and β=121.45° (1). Despite its lower symmetry, [Ce(Suc)] presents an important structural filiation with [Sm(Suc)]  相似文献   

12.
Compound [Ni(hmt)2(SCN)2(H2O)2][Ni(SCN)2(H2O)4](H2O)2 (hmt=hexamethylenetetramine) was pre-pared and structurally characterized by means of X-ray single crystal diffraction. The two neutral units [Ni(hmt)2(SCN)2(H2O)2] and [Ni(SCN)2(H2O)4] are joined together through hydrogen bonds N…H-O, O…H-O and S…H-O. In the solid state, the compound has three-dimensional network structure. The determination of its variable-temperature magnetic susceptibilities (5~300K) shows that the magnetic behavior obeys the Curie-Weiss law over the whole temperature ranges.  相似文献   

13.
Thermolysis of Cu(NO3)2·3H2O is studied by means of XRD analysis in situ and mass spectral analysis of the gas phase at P=1/10 Pa at low heating rate. It is shown that stage I of the dehydration (40-80 °C) results in the consecutive appearance of crystalline Cu(NO3)2·2.5H2O and Cu(NO3)·H2O. Anhydrous Cu(NO3)2 formed during further dehydration at 80-110 °C is moderately sublimed at 120-150 °C. Dehydration is accompanied by thermohydrolysis, leading to the appearance of Cu2(OH)3NO3 and gaseous H2O, HNO3, NO2, and H2O. The higher pressure in the system, the larger amount of thermohydrolysis products is observed. The formation of the crystalline intermediate CuOx(NO3)y was observed by diffraction methods. Final product of thermolysis (CuO) is formed at 200-250 °C.  相似文献   

14.
The complex [Re2(HPO4)2(H2PO4)2(H2O)2] · 4H2O (I) was synthesized and investigated by conductometric, potentiometric, electronic and vibration spectroscopic methods. Thermal behavior of the title compound was studied and its molecular structure was determined from X-ray diffraction data. In the dimeric neutral complex, the bridging pairs of the hydrophosphate and dihydrophosphate groups close four five-membered Re-O-P-O-Re chelate rings. The O atom of water molecule occupies the axial position in the metal coordination polyhedron. The Re-Re distance 2.2168(8) ? corresponds to quadruple bond. Original Russian Text ? A.V. Shtemenko, V.G. Stolyarenko, K.V. Domasevich, 2007, published in Koordinatsionnaya Khimiya, 2007, Vol. 33, No. 2, pp. 83–88.  相似文献   

15.
[Pb2(TNR)(NO3)2(H2O)] was prepared by reaction of the aqueous solution of lead nitrate and magnesium styphnate. The crystal structure of Pb2(TNR)(NO3)2(H2O)was determined by single crystal diffraction analysis. The crystal is triclinic, space group P1 with crystal parameters a=0.7279(2)nm,b=1.0698(2)nm,c=1.0738(2)nm;α=86.82(1)°,β=89.52(2)°,γ=83.50(2)°;V=0.8295(3)nm3,Z=2,Dc=3.201g·cm-3, F(000)=716. The final R value is 0.0358.In the crystal structure, one lead ion was represented by nine coor-dination geometry; the other was showed as ten coordination geometry.  相似文献   

16.
[H3O][Ce(SO4)2] · H2O crystallizes in the monoclinic system with unit-cell dimensions (from single-crystal data) a = 9.359(4), b = 9.926(4), c = 8.444(3) Å, β = 96.53(9)° and space group P21/n, z = 4. The structure was solved by conventional heavy-atom methods using 1787 counter-measured reflections (MoKα radiation), and refined using full-matrix least-squares techniques to an R of 0.0465 (ωR = 0.0413). The structure consists of cerium(III) ions in irregular nine-coordination to oxygen atoms from two bidentate sulfate ions, four monodentate sulfate oxygen atoms, and one water molecule. The oxonium ions are present as isolated ions in the structure and take par in the hydrogen bonding network. The Ce-O bond lengths range from 2.454(7) to 2.626(6) Å.  相似文献   

17.
Synthesis, structure, spectroscopy and thermal properties of complex [Co(NCS)2(hmt)2(H2O)2][Co(NCS)2(H2O)4] (H2O) (I), assembled by hexamethylenetetramine and octahedral Co(II) metal ions, are reported. Crystal data for I: Fw 387.34, a=9.020(8), b=12.887(9), c=7.95(1) Å, =96.73(4), β=115.36(5), γ=94.16(4)°, V=820(1) Å3, Z=2, space group=P−1, T=173 K, λ(Mo-K)=0.71070 Å, ρcalc=1.718567 g cm−3, μ=17.44 cm−1, R=0.088, Rw=0.148. An interesting two-dimensional network is assembled via hydrogen bonds through coordinated and free water molecules. The d–d transition energy levels of Co(II) ion are determined by UV–vis spectroscopy and calculated by ligand field theory. The calculated results agree well with experiment ones.  相似文献   

18.
A complex of the composition KNa3[Fe3O(CH3COO)6(H2O)3]3 [α-P2W17Fe(H2O)O61]·32.5H2O (I) was obtained by interaction of FeCl3·6H2O and phosphotungstate K102-P2W17O61]·20H2O in an acetate buffer with a yield of 52%. Compound I was characterized by single crystal X-ray phase analysis and IR spectroscopy. In the crystal structure, the Na and K cations bind [Fe3O(CH3COO)6(H2O)3]+ trinuclear cations and [α-P2W17Fe(H2O)O61]7− heteropolytungstate anions into infinite zigzag chains. Original Russian Text Copyright ? 2005 by N. V. Izarova, M. N. Sokolov, A. V. Virovets, H. G. Platas, and V. P. Fedin __________ Translated from Zhurnal Strukturnoi Khimii, Vol. 46, No. 1, pp. 149–155, January–February, 2005.  相似文献   

19.
The structure of the product formed on boiling [RuNO(NH3)3(NO2)(OH)]Cl·0.5H2O in 3 M HNO3 is determined by XRD. The crystals belong to monoclinic symmetry. Crystallographic data for H11ClN6O8Ru are: a = 13.7924(4) ?, b = 6.9114(2) ?, c = 12.3577(4) ?, β = 111.863(1)°, V = 1093.27(6) ?3, Z = 4, d calc = 2.185 g/cm3, space group Cc. The structure is built of complex [RuNO(NH3)3(H2O)Cl]2+ cations and NO3 anions. The compound is studied by IR spectroscopy and X-ray phase analysis. Original Russian Text Copyright ? 2009 by V. A. Emel’yanov, E. V. Kabin, and I. A. Baidina __________ Translated from Zhurnal Strukturnoi Khimii, Vol. 50, No. 3, pp. 598–601, May–June, 2009.  相似文献   

20.
In this paper we describe the molecular and crystal structures of the K3[Y(NTA)2(H2O)]· 6H2O(H3NTA=nitrilotriacetic acid). The crystal data are as followsmonoclinic system, C2/c space group, a=1.5268(3)nm,b=1.2833(3)nm,c=2.6079(5)nm,β =96.03(3)°,V=5.0815(18)nm3,Z=8,M=708.68,Dc=1.852gcm-3,μ =2.875mm-1,F(000)=2880.The final R1 and wR2 are 0.0636 and 0.1523 for 4264 [I >2.0σ (I)] unique reflections and 0.1178 and 0.1651 for all 4364 reflections,respectively.In the title complex, the anion [Y(NTA)2(H2O)]3- has a nine-coordination structure with distorted monocapped square antiprism. Each group acts as a tetradentate ligand with three Oatoms and one Natom and a H2O molecule caps a quadrilateral face as a ligand.It can be known that the Y(Ⅲ) ion can form a high-coordinate compound with aminopolycarboxylic acid ligands because it has a larger ionic radius (0.104nm).  相似文献   

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