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1.
An inclusion compound of constant composition [Ni(DBM)2Py2]·2(CH3COCH3) is synthesized, Ni = Ni(II), DBM is dibenzoylmethanate-anion (C6H5CO)2CH?, Py is pyridine. The compound and its dissociation products are examined by structural and thermal analysis, as well as vapor pressure measurements. The crystal structure of the clathrate is solved in the monoclinic space group P21/n (temperature 173 K, a = 11.8617(9) Å, b = 10.0096(6) Å, c = 17.2895(9) Å, β = 96.72(1)°, V = 2038.7(2) Å3, Z = 2, final R 1 = 0.032). The host molecule [Ni(DBM)2Py2] is an uncharged octahedral complex, the central Ni(II) atom being surrounded by two DBM-anions in the equatorial plane and two terminal pyridines in the axial positions. Pairs of guest molecules are located in the voids of the molecular crystal. Calculated packing coefficients of the clathrate and the stable form of the host complex are 0.685(2) and 0.668(1) at 173 K, respectively. Isochoric melting of the clathrate has incongruent nature and occurs at 58–60°C to yield the solid phase of the host complex, while in air the complex decomposes in gaseous acetone and a metastable form of the host (apohost). The collapse of the metastable form of [Ni(DBM)2Py2] to the stable one takes place at 131°C with the release of 11 kJ/mol. The equilibrium vapor pressure of acetone over the clathrate is measured with the spoon gauge technique in a temperature interval from 292 K to 310 K (at 298 K the pressure is 0.48P 0, P 0 is the saturated vapor pressure of liquid acetone at this temperature). The experimental dependence logP ? 1/T is used to derive thermodynamic parameters of the process of clathrate dissociation 1/2[Ni(DBM)2Py2]· 2(CH3COCH3)(s) = 1/2[Ni(DBM)2Py2](s) + CH3COCH3(gas): ΔH av 0 = 53±3 kJ/mol, ΔS av 0 = 160±10 J/(mol·K), ΔG 298 0 = 4.74±0.07 kJ/mol.  相似文献   

2.
We describe the preparation and crystal structures of the ionic complexes [Cu(bipy)2{ONC(CN)2}]CF3SO3 (1b), [Cu(phen)2{ONC(CN)2}]PF6 (2p) and [Cu(bipy)2{ONC(CN)2}]PF6 (2b). In the complex cations [Cu(L)2{ONC(CN)2}]+ (L is 2,2′-bipyridine (bipy) or 1,10-phenanthroline (phen)) the two molecules of bipy or phen coordinate to the copper atom through two nitrogen atoms along with the oxygen atom of the nitrosodicyanomethanide anion, ONC(CN) 2 ? , to form a {CuN4O} chromophore with a distorted square pyramidal coordination sphere in (1b) and (2b) and a distorted trigonal bipyramidal geometry in (2p). The basal plane in (1b) and (2b) is formed by an oxygen atom coordinated at the Cu1–O1 distance of 1.990(2) and 2.002(2) Å, respectively, and three nitrogen atoms coordinated to the copper atom at similar distances with the average of 2.01(2) and 2.00(3) Å, respectively. The axial position is occupied by the fourth N atom at the longer distance of 2.222(2) and 2.185(2) Å, respectively. The trifluoromethanesulfonate anion (triflate), CF3SO 3 ? , in (1b) might be considered as very weakly coordinated in the opposite axial position (Cu1–O2 = 2.719(2) Å). The equatorial plane in (2p) is formed by an oxygen atom coordinated at the Cu1–O1 distance of 1.975(3) Å, and two nitrogen atoms from different phen molecules coordinated to the copper atom at the same distance within 2 σ with the average distance of 2.124(2) Å. The axial positions are occupied by remaining two nitrogen atoms coordinated at shorter distance (average Cu–N = 1.99(3) Å). The hexafluorophosphate anions, PF 6 ? , in (2p) and (2b) remain uncoordinated. Besides the ionic forces, the structures of (2p) and (2b) may be stabilized by very weak C–H···F whereas the structure of (1b) by very weak C–H···F, C–H···O and C–H···N hydrogen bonds. The structural–spectral correlations are also discussed.  相似文献   

3.
The crystal structure of bis(semicarbazido)copper(II) nitrate [Cu(NH2NHC(O)NH2)2](NO3)2 has been studied by X-ray diffraction. Monoclinic crystals, a = 6.835(2) Å, b = 7.733(2) Å, c = 10.320(3) Å, β = 105.701(3)°, V = 525.1(2) Å3, space group P21/c, Z = 2, d msd = 2.136 g/cm3, μ(MoK α) = 2.143 mm−1. The structure was solved with the program for automatic analysis of Patterson’s function and refined by full-matrix least squares in an anisotropic approximation for all non-hydrogen atoms using 753 independent reflections; R 1 = 0.0203. The square environment of the Cu atom is formed from the amino nitrogen atoms of the hydrazine fragments and the C=O oxygen atoms of the two semicarbazide bidentate molecules (Cu-N 1.928 Å, Cu-O 1.999 Å). The axial positions are occupied by the O atoms of the NO 3 outer-spheric anions (Cu-O 2.505 Å). In the structure, the complex cations and the NO 3 anions are linked into a framework by N-H...O type hydrogen bonds. Original Russian Text Copyright ? 2007 by G. V. Romanenko, Z. A. Savelieva, and S. V. Larionov __________ Translated from Zhurnal Strukturnoi Khimii, Vol. 48, No. 2, pp. 370–373, March–April, 2007.  相似文献   

4.
The temperature dependence of the saturated vapor pressure of the trans-Pt(ktf)2 complex obtained from fluorinated β-ketoimine (CF3-CO-CH2-C(NH)-CH3) was studied by the flow method. The standard thermodynamic parameters ΔH 0 T and ΔS 0 T of sublimation have been determined. Full crystal-chemical study has been performed for the complex. Crystal data for C10H10F6N2O2Pt: a = 5.9790(8) Å, b = 7.373(2) Å, c = 8.5767(2) Å,α = 84.05(2)°, β = 72.43(1)°, γ = 67.14(1)°, V = 332.1(1) Å3, Z = 1, dcalc = 2.496 g/cm3, triclinic, space group \(P\bar 1\). The structure is molecular and consists of isolated trans-Pt(ktf)2 complexes. The Pt atom lies at the symmetry center and has a square planar environment of two oxygen and two nitrogen atoms; the distances Pt-O (1.984 Å) and Pt-N (1.969 Å) are similar within the limits of 2σ; the OPtN bond angle is 93.9°. Molecular packing in crystal is considered based on structural data; van der Waals energy of the crystal lattice of trans-Pt(ktf)2 was calculated by the atom-atom potential method.  相似文献   

5.
The [Ag(Bpp)](CF3CO2) complex (Bpp is 1,3-bis(4-pyridyl)propane, C13H14N2) is synthesized, and its structure is determined. The crystals are monoclinic, space group C2/c, a = 26.169(5), b = 10.521(2), c = 12.906(3) Å, β = 117.99(3)°, V = 3137.7(11) Å3, ρcalcd = 1.775 g/cm3, Z = 8. The structure contains double helices of-Ag-Bpp-Ag-Bpp-cationic chains with a helix period of 21.042 Å. The Ag…Ag distance between a pair of silver atoms from different chains in the helix is 3.201 Å, and the distance between the adjacent helices is 3.279 Å. The silver atom is linked with two bridging nitrogen atoms of two Bpp ligands in an almost linear coordination: Ag-Navg 2.142 Å; NagN, 171.3(4)°. The CF3C 2 ? anion has a weak contact with the silver ion (Ag…O 2.62(2) Å).  相似文献   

6.
Synthesis and results of the single crystal X-ray diffraction study of iron(III) pivaloyltrifluoroacetonate are reported. Crystal data for C24H30FeF9O6: a = 9.2205(6) Å, b = 9.6584(10) Å, c = 17.3799(17) Å, α = 75.902(2)°, β = 80.517(3)°, γ = 82.746(3)°, space group P-1, V = 1474.6(2) Å3, Z = 2. The structure is molecular with the octahedral environment of Fe atom, Fe-Oav 1.991 Å, ∠O-Fe-Oav 86.48°. The van der Waals energy of intermolecular interactions is calculated and compared to thermodynamic data.  相似文献   

7.
The structure of tris{hexachloridostannate(IV)}-hexachloride-tetrakis(pefloxacinium)-tetraoxonium undecahydrate (CCDC 1551760) 4PefH 3 2+ , 4H3O+, 3SnCl 6 2? , 6Cl?, 11H2O (I), (PefH is pefloxacin) is determined. The I crystals are triclinic: a = 13.5474(10) Å, b = 15.2859(11) Å, c = 15.6586(11) Å, α = 94.467(1)°, β = 105.477(1)°, γ = 111.560(1)°, V = 2849.9(4) Å3, space group Pī, Z = 1. The structure is stabilized by multiple intermolecular hydrogen bonds and π–π-interactions between the PefH32+ ions.  相似文献   

8.
New ferrites ErMFe2O5 (M = Li, Na, K) were synthesized from erbium and iron(III) oxides and lithium, sodium, and potassium carbonates by solid-state annealing. According to X-ray powder diffraction, these compounds crystallize in the orthorhombic system with the following unit cell parameters: ErLiFe2O5, a = 10.510 Å, b = 10.776 Å, c = 14.270 Å, V 0 = 1616.16 Å3; Z = 16, V subcell 0 = 101.01 Å3, ρX = 6.01 g/cm3, ρpycn = 5.97 ± 0.05 g/cm3; ErNaFe2O5, a = 10.519 Å, b = 10.785 Å, c = 15.510 Å, V 0 = 1759.56 Å3, Z = 16, V subcell 0 = 109.90 Å3, ρX = 5.77 g/cm3, ρpycn = 5.72 ± 0.08 g/cm3; ErKFe2O5, a = 10.050 Å, b = 11.320 Å, c = 15.480 Å, V 0 = 1937.33 Å3, Z = 16, V subcell 0 = 121.08 Å3, ρX = 5.46 g/cm3, ρpycn = 5.41 ± 0.04 g/cm3.  相似文献   

9.
Ferrites of composition ErMIFe2O5 (MI = Li, Na, K, Cs) were synthesized by a solid-phase method. The structure of the ferrites was for the first time studied by X-ray powder diffraction. Crystal systems, unit cell parameters, and X-ray and pycnometric densities were determined. For ErLiFe2O5, a = 10.510 Å, c = 14.270 Å, V°= 1616.16 Å3, Z = 16, V subcell ° = 101.01 Å3, ρx = 6.01 g/cm3, ρpyc = 5.97 ± 0.04 g/cm3; for ErNaFe2O5, a = 10.519 Å, c = 15.510 Å, V° = 1759.56 Å3, Z = 16, V subcell ° = 109.90 Å3, ρx = 5.77 g/cm3, ρpyc = 5.72 ± 0.08 g/cm3; for ErKFe2O5, a = 11.050 Å, c = 15.480 Å, V° = 1937.33 Å3, Z = 16, V subcell ° = 121.08 Å3, ρx = 5.46 g/cm3, ρpyc = 5.41 ± 0.04 g/cm3; and for ErCsFe2O5, a = 10.78 Å, c = 16.01 Å, V° = 1905.37 Å3, Z = 16, V subcell ° = 119.09 Å3, ρx = 6.86 g/cm3, ρpyc = 6.61 ± 0.01 g/cm3.  相似文献   

10.
In the work, isomeric complexes of platinum(II) with the (ptac)–1 pivaloyltrifluoroacetonate ion (Pt((CH3)3–CO–CH–CO–CF3)2) are studied. The synthesis and chromatographic separation of Pt(ptac)2 isomers are described, TGA data for the separated isomers are given, and the crystal structures of the solid phases are studied. The cis-Pt(ptac)2 complex crystallizes in the space group P-1, a = 10.7091(4) Å, b = 12.7787(6) Å, c = 16.0154(8) Å, α = 92.389(2)°, β = 90.868(2)°, γ = 112.1260(10)°, V = 2027.39(16) Å3, Z = 4, d calc = 1.918 g/cm3. The trans-Pt(ptac)2 complex crystallizes in the space group C2/m, a = 13.3235(5) Å, b = 8.5515(3) Å, c = 9.6694(3) Å, β = 118.5880(10)°, V = 967.38(6) Å3, Z = 2, d calc = 2.010 g/cm3. The structures of the complexes are molecular, the Pt atom has a square coordination of four oxygen atoms of two ligands; for cis-Pt(ptac)2, the Pt–Oav distance is 1.968 Å, for trans-Pt(ptac)2 it is 1.980 Å.  相似文献   

11.
X-ray structural analysis has been performed for two complex compounds: Cu(en)2(o-HB)2H2O (I) (a = 16.873(4) Å, b = 8.713(2) Å, c = 14.803(3) Å, β = 91.15(2)°, V = 2175.8(8) Å3, C2/c, Z = 4, R(F) = 0.0263, 1516 reflections with I > 3σ (I)) and [Cu(en)2(OH2)2]2+(o-AB?)2 (II) (a = 7.488(5) Å, b = 22.122(8) Å, c = 7.856(5) Å, β = 118.77(2)°, V = 1140.7(11) Å3, P21/n, Z = 2, R(F) = 0.0432, 1684 reflections with I > 3σ(I)) synthesized under identical conditions (en is ethylenediamine, o-HB is o-hydroxybenzoate, and o-AB is o-aminobenzoate). Although the compounds were assumed to have similar structures and the Cu-Lig bond lengths and the cis and trans angles are acceptable for an octahedral structure, the geometric parameters of o-HB suggest that the copper atom has a plane square environment.  相似文献   

12.
Copper(II) chelates with β-diimine derivatives of acetylacetone that have a general formula of Cu(R1C(NR2)CHC(NR2)R1)2, where R1, R2 are alkyl substituents, are synthesized. The complexes were identified using elemental analysis, melting point measurements, and high-temperature mass spectrometry data. Knudsen technique is employed to determine the vapor pressure temperature dependence, and standard thermodynamic parameters of sublimation ΔH T 0 and ΔS T 0 are derived. A single crystal X-ray diffraction study is carried out for copper(II) complexes of Cu(CH3-C(NCH3)-CH-C(NCH3)-CH3)2 (a = 10.363(1) Å, b = 11.978(1) Å, c = 12.653(1) Å, V = 1570.6(3) Å3, space group Pnc2, Z = 4, d calc = 1.328 g/cm3, R = 0.027), Cu(CH3-C(NC2H5)-CH-C(NC2H5)-CH3)2 (a = 11.782(4) Å, b = 13.951(8) Å, c = 25.591(8) Å, V = 4206(3) Å3, space group C2221, Z = 8, d calc = 1.169 g/cm3, R = 0.10), and also 2-(methylamino)-4-(methylimino)-pentene-2 CH3-(C=(NCH3))-CH=(C-(NHCH3))-CH3 (a = 12.129(2) Å, b = 12.034(2) Å, c = 5.692(1) Å, β = 107.05(3)°, V = 794.3(3) Å3, space group Cc, Z = 4, d calc = 1.055 g/cm3, R = 0.06). Van der Waals lattice energy E cryst is calculated for the cooper(II) complexes by the atom-atom potential technique. The calculated values are compared to experimental sublimation enthalpies Δ H T 0 .  相似文献   

13.
The crystal structure of (hexafluoroacetylacetonato)(pivaloylacetonato)copper(II) has been determined. Crystal data for CuO4C13H14F6: a = 8.288(2) Å, b = 8.682(2) Å, c = 12.307(2) Å; α = 90.75(3)°, β = 94.29(3)°, γ = 106.60(3)°; V = 845.7(3) Å3, space group \(P\overline 1 \), Z = 2, dcalc = 1.617 g/cm3. The coordination polyhedron of the copper atom is formed by four oxygen atoms of two different β-diketonate ligands with Cu-O distances within 1.874–1.946 Å; the O-Cu-O bond angles are 94.8° and 90.6°. The complexes are united into centrosymmetrical “dimers” with Cu...Cu distances of 4.365 Å.  相似文献   

14.
Triclinic modification of trans-bis(trifluoroacetylacetonato)copper(II) is studied by single crystal X-ray diffraction (diffractometer X8 APEX BRUKER, MoK α radiation, T = 173(2) K). The structure is molecular. Square environment of the Cu atom (Cu-Oav 1.916 Å, ∠O-Cu-Oav 93.4°) is completed to a bipyramid by two atoms of neighboring molecules, Cu...Cγ 3.18 Å and 3.23 Å.  相似文献   

15.
Compound [Zn(CF3CO2)2(Bpp)2], where Bpp is 1,3-bis(4-pyridyl)propane, was synthesized and its structure and luminescent properties were determined. Crystals are monoclinic, space group C2/c, a = 21.261(1) Å, b = 17.642(1) Å, c = 18.632(1) Å, β = 115.85(1)°, V = 6289.3(6) Å3, ρcalcd = 1.453 g/cm3, Z = 8. The structure comprises 2D neutral layers of conjugated multiunit rings composed of four Zn2+ ions united by four bridging Bpp ligands. Each of two crystallographically nonequivalent Zn atoms is coordinated at the octahedra apices to four nitrogen atoms of two Bpp ligands and two O(CF3CO2) atoms. Trifluoroacetate anions are coordinated to Zn2+ ions in monodentate manner. The compound exhibits photoluminescence in solid state.  相似文献   

16.
Coordination polymers [Ag(C4H10N2)]ReO4 (I) and [Ag(C4H10N2)]PF6 (II) (C4H10N2 is piperazine, Ppz) were synthesized and their structures were determined. Crystals of compound I are monoclinic, space group P21/c, a = 6.207(1) Å, b = 12.533(1) Å, c = 11.386(1) Å, β = 93.41(1)°, V = 884.2(2) Å3, ρcalc = 3.337 g/cm3, Z = 4. Crystals of II are monoclinic, space group C2/m, a = 8.723(1) Å, b = 9.083(1) Å, c = 5.797(1) Å, β = 95.07(1)°, V = 457.5(1) Å3, ρcalc = 2.548 g/cm3, Z = 2. Structure I contains polymer chains [Ag(Ppz)] + . The silver atom is linked with two nitrogen atoms of the adjacent Ppz ligands to form a nearly linear fragment; the Ag-Nav distance is 2.173 Å, and the NAgN angle is 169.4(3)°. The chains are linked with each other by weak interactions Ag…O(ReO4) (2.643(8) Å) and N-H…O hydrogen bonds. The structure of compound II also contains cationic polymer chains [Ag(Ppz)] + . The Ag+ ion is located in the inversion center and has a linear coordination (Ag-N distance is 2.171(9) Å). The central P atom of the octahedral fluorophos-phate ion is also located in the inversion center; the anion is slightly distorted and has no contacts with silver ions at a distance <3.4 Å.  相似文献   

17.
Complex [Ag(CF3CO2)(C5H5N3O)] (I) was synthesized, and its structure was determined. Crystals of complex I are triclinic, space group P \(\bar 1\),,a = 7.325(1) Å, b = 7.554(1) Å, c = 10.527(1) Å, α = 94.25(1)°, β = 96.19(1)°, γ = 117.75(1)°, V = 507.4(1) Å3, ρcalcd = 2.252 g/cm3, Z = 2. Structure I contains dimeric silver carboxylates Ag2(C5H5N3O) 2 2+ , formed by 2-pyrimidinecarboxamide. Adjacent dimers Ag2(C5H5N3O) 2 2+ are linked by carboxylate dimers to form infinite ribbons along the x axis. The ribbons are arranged in the structure so that cavities are formed between them in the [001] direction. Trifluoroacetate CF3 groups and carboxamide NH2 groups are directed into the inside of these cavities.  相似文献   

18.
The crystal structure of [Cu(En)2CrO4]n (En is ethylenediamine) is determined: a = 14.7359(4) Å, b = 9.8083(3) Å, c = 14.2664(4) Å, V = 2061.98(10) Å3, space group Cmce, Z = 8, dx = 1.931 g/cm3. It is demonstrated that the studied phase is isostructural with [Сu(Еn)2SO4]n. A pseudotetragonal copper atom coordination (Cu–N 2.0204 Å and 2.0244 Å, ∠N–Cu–N 84.73°) is completed to distorted octahedral by two oxygen atoms of chromate anions (Cu–O 2.433 Å and 2.380 Å).  相似文献   

19.
The complex [Ag(2-MePyz)ReO4] (I) is synthesized, and its structure is determined. The crystals are monoclinic, space group P 21/c, a = 7.234(1), b = 15.451(1), c = 8.036(3) Å, β = 92.56(1)°, V = 897.3(2) Å3, ρcalcd = 3.347 g/cm3, Z = 4. Structure I consists of cationic polymer chains [Ag(2-MePyz)] + . Anions ReO 4 ? are weakly bound to Ag+ (Ag...Oaverage 2.693 Å) and join the latter into a supramolecular framework. The Ag+ ion has a linear coordination (NAgN 177.9(2)°, distances Ag-N 2.223(5) and 2.242(5) Å).  相似文献   

20.
Heteroligand complexes [Co2(HMTA)(iso-Bu2PS2)4] (I) (μeff = 4.67 μB) and [Cd2(HMTA)(iso-Bu2PS2)4] (II) have been synthesized. Single crystals of compounds I and II have been obtained. The crystals are monoclinic: a = 32.622(2) Å, b = 9.4891(6) Å, c = 21.7570(13) Å, β = 125.774(1)o, V = 5464.3(6) Å,3, Z = 4, ρcalcd = 1.331 g/cm3 for I; a = 34.6092(7) Å, b = 9.5595(2) Å, c = 22.3473(5) Å, β = 127.144(1)o, V = 5893.5(2) Å, Z = 4, ρcalcd = 1.355 g/cm3 for II; space group for both complexes C2/c. Structures I and II are based on discrete binuclear molecules. The coordination polyhedra of the Co and Cd atoms are distorted tetragonal pyramids NS4, with the bases formed by four S atoms of two bidentate chelating ligand iso-Bu2PS 2 ? and the axial vertices occupied by N atoms of bidentate bridging HMTA ligand. The character of interaction of the molecules in structures I and II is considered.  相似文献   

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