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1.
Two crystalline modifications (I and II) of the phenanthroline complex of erbium nitrate with the same chemical composition, Er(NO3)3(Phen)2, are synthesized by a procedure similar to that used for preparing the phenanthroline complexes of europium nitrate. The crystal structures of these modifications are determined using X-ray diffraction. Crystals of compound I belong to the isostructural family Ln(NO3)3(Phen)2 (Ln = La-Lu). Crystals of compound II are isostructural to those of modification II (new phase) of the Eu(NO3)3(Phen)2 compound. Crystals of I and II are monoclinic, space group C2/c, and Z = 4. The unit cell parameters are as follows: a = 11.126 Å, b = 17.815 Å, c = 12.976 Å, β = 100.45°, and V = 2529 Å3 for modification I and a = 9.459 Å, b = 15.463 Å, c = 17.076 Å, β = 93.52°, and V = 2493 Å3 for modification II. The molecular complexes in the structures of compounds I and II are nearly identical. The mean lengths of the Er-N and Er-O bonds are equal to 2.500 and 2.466 Å in compound I and 2.508 and 2.457 Å in compound II, respectively. The difference between the structures of compounds I and II is associated with the difference between intermolecular interactions in the unit cell.  相似文献   

2.
-The crystal structures of mixed coordination compounds, Cu(2)Gly(D-Ser)(L-Ser)2(I) and Cu(2)Gly 3(L-Ser)(II), which contain the amino acid residues of glycine (Gly) and serine (Ser) in the 1: 3 and 3: 1 ratio, respectively, are studied by electron diffraction. Crystals I and II are triclinic, Z = 1, and space group P1. For I, a = 8.96(2) Å, b = 9.66(2) Å, c = 5.07(2) Å, α = β = 90°, and γ = 92.8(3)°. For II, a = 8.37(2) Å, b = 9.65(2) Å, c = 5.06(2) Å, α = β = 90°, and γ = 92.8(3)°. Compounds I and II have layered structures that are based on the CuGly(L-Ser) fragment. Structures I and II differ mainly in their interlayer spacing and configuration of the interlayer space.  相似文献   

3.
The para and ortho isomers of 3,5-dinitro-(4-acetylphenyl)aminobenzoyl (p-bromophenyl)amide (I and II, respectively) are synthesized, and their physicochemical properties and structure are investigated. The para isomer I has a higher melting temperature and is less soluble in organic solvents as compared to the ortho isomer II. The electronic absorption spectra indicate that absorption for molecule I occurs at longer wavelengths than for molecule II. A correlation between the physicochemical properties and the crystal structures of compounds I and II is revealed. Crystals I · 0.5C6H6 are triclinic; the unit cell parameters are a = 11.760(2) Å, b = 13.958(3) Å, c = 15.012(3) Å, α = 108.01(2)°, β = 103.95(1)°, γ = 92.00(2)°, V = 2258.3(8) Å3, space group $P\bar 1$ , and Z = 4. Crystals II are monoclinic; the unit cell parameters are a = 9.302(2) Å, b = 16.380(3) Å, c = 13.480(3) Å, β = 100.09(3)°, V = 2022.1(7) Å3, space group P21/c, and Z = 4. Structures I · 0.5C6H6 and II are characterized by intramolecular and intermolecular hydrogen bonds.  相似文献   

4.
Double potassium indium and rubidium indium phosphates K3In(PO4)2 (I) and Rb3In(PO4)2 (II) are synthesized by solid-phase sintering at T = 900°C. The compounds prepared are characterized by X-ray powder diffraction (I and II), X-ray single-crystal diffraction (II), and laser-radiation second harmonic generation. Structure I is solved using the Patterson function and refined by the Rietveld method. Both compounds crystallize in the monoclinic crystal system. For crystals I, the unit cell parameters are as follows: a = 15.6411(1) Å, b = 11.1909(1) Å, c = 9.6981(1) Å, β = 90.119(1)°, space group C2/c, R p = 4.02%, and R wp = 5.25%. For crystals II, the unit cell parameters are as follows: a = 9.965(2) Å, b = 11.612(2) Å, c = 15.902(3) Å, β = 90.30(3)°, space group P21/n, R 1 = 4.43%, and wR 2 = 10.76%. Structures I and II exhibit a similar topology of the networks which are built up of { In[PO4]2} (I) and { In2[PO4]4} (II) structural units.  相似文献   

5.
Two cadmium halide complexes with 1,2-bis[2-(diphenylphosphinylmethyl)phenoxy]ethane (L 1) and 1,3-bis[2-(diphenylphosphinylmethyl)phenoxy]propane (L), namely, CdBr2 ? L 1 (I) and CdI2 ? L(II), have been synthesized. An analysis of their vibrational spectra is carried out. The structures of I and II are determined by X-ray diffraction. Crystals I are monoclinic, a = 31.562(6) Å, b = 13.548(3) Å, c = 18.733(4) Å, β = 91.28(3)°, space group C2/c, Z = 8, and R = 0.051 for 3776 reflections. Crystals II are triclinic, a = 11.803(2) Å, b = 12.554(3) Å, c = 14.686(3) Å, α = 90.30(3)°, β = 90.29(3)°, γ = 106.08(3)°, space group $P\bar 1$ , Z = 2, and R = 0.043 for 4916 reflections. Compounds I and II exhibit a polymeric chain structure. The potentially tetradentate ligands L 1 and L are coordinated to the metal atoms only through two phosphoryl oxygen atoms and fulfill the bidentate bridging function. The environment of the Cd atom is completed to the tetrahedral coordination by two Br atoms in complex I and two I atoms in complex II. The mean distances are as follows: Cd-Br, 2.526(2) Å; Cd-I, 2.695 Å; and Cd-O, 2.243(8) Å in I and 2.210(4) Å in II. The L 1 and L ligands in complexes I and II adopt an S-shaped conformation.  相似文献   

6.
Single crystals of UO2(n-C3H7COO)2(H2O)2 (I) and Mg(H2O)6[UO2(n-C3H7COO)3]2 (II) are synthesized. Their IR-spectroscopic and X-ray diffraction studies are performed. Crystals I are monoclinic, a = 9.8124(7) Å, b = 19.2394(14) Å, c = 12.9251(11) Å, β = 122.423(1)°, space group P21/c, Z = 6, and R = 0.0268. Crystals II are cubic, a = 15.6935(6) Å, space group $Pa\bar 3$ , Z = 4, and R = 0.0173. The main structural units of I and II are [UO2(C3H7COO)2(H2O)2] molecules and [UO2(C3H7COO)3]? anionic complexes, respectively, which belong to AB 2 01 M 2 1 (I) and AB 3 01 (II) crystal chemical groups of uranyl complexes (A = UO 2 2+ , B 01 = C3H7COO?, and M 1 = H2O). A crystal chemical analysis of UO2 L 2 · nH2O compounds, where L is a carboxylate ion, is performed.  相似文献   

7.
The crystal structures of Cs[CuB10H10] (I) and (CH3)2NH2[CuB10H10] (II) are studied (R = 0.0398 and 0.0510 for 1225 and 2728 observed reflections in I and II, respectively). Crystals I and II are built of [(CuB10H10)?]∞ anionic chains and cations. The distorted tetrahedral coordination of the Cu+ ions is formed by four pairs of B-H atoms from two polyhedral anions. The Cu-B bond lengths in I and II are 2.159–2.287(6) and 2.130–2.285(9) Å, respectively. The coordination of the Cu+ ions in II includes only edges between apical and equatorial vertices of the anions. In I, both the edges of the apical belt and those between two equatorial vertices are involved in coordination. The ability of the B10H 10 2? anion to coordinate metals by the equatorial edge is established for the first time.  相似文献   

8.
Bis(acetylacetonato)oxovanadium C10H14O5V (I) and (S)-[2-(N-salicylidene)aminopropionate]oxovanadium monohydrate C10H9NO5V (II) are synthesized. The crystal structures of compounds I and II are determined using single-crystal X-ray diffraction. Crystals of compound I are triclinic, a = 7.4997(19) Å, b = 8.2015(15) Å, c = 11.339(3) Å, α = 91.37(2)°, β = 110.36(2)°, γ = 113.33(2)°, Z = 2, and space group \(P\bar 1\). Crystals of compound II are monoclinic, a = 8.5106(16) Å, b = 7.373(2) Å, c = 9.1941(16) Å, β = 101.88(1)°, Z = 2, and space group P21. The structures of compounds I and II are solved by direct methods and refined to R1 = 0.0382 and 0.0386, respectively. The oxovanadium complexes synthesized are investigated by vibrational spectroscopy.  相似文献   

9.
The crystal structures of 1-acetoxy-1-cyano-2-naphthylethylene (I) and 1,1-dicyano-2-naphthylethylene (II) are determined by X-ray structure analysis. Crystals I are monoclinic; at 25° C, the unit cell parameters are as follows: a = 17.308(6) Å, b = 4.507(1) Å, c = 17.845(5) Å, β = 107.90(2)°, V = 1324.7(7) Å3, d calcd = 1.260 g/cm3, Z = 4, and space group P21/n. Crystals II are monoclinic; at 25°C, the unit cell parameters are a = 3.827(1) Å, b = 15.784(4) Å, c = 17.226(2) Å, β = 91.22(2)°, V = 1040.3(4) Å3, d calcd = 1.304 g/cm3, Z = 4, and space group P21/n. It is revealed that, in crystal structures of I and II, the molecular stacks characteristic of compounds of this series are formed through stacking contacts along the direction of the smallest lattice parameter.  相似文献   

10.
The crystal structures of two host-guest molecular complexes of 18-crown-6 with 2-aminobenzoic acid hydrazide monohydrate (the ratio host: guest: H2O = 1: 2: 2) (complex I) and 5-amino-1-benzyl-1,2,3-triazole-4-carboxylic acid hydrazide (the host: guest ratio = 1: 2) (complex II) are determined by X-ray diffraction analysis. Crystals I are monoclinic, a = 8.468(2) Å, b = 17.378(3) Å, c = 10.517(2) Å, β = 96.88(3)°, space group P21/n, and R = 0.0393 for 6692 reflections. Crystals II are orthorhombic, a = 18.489(1) Å, b = 10.192(3) Å, c = 20.412(2) Å, space group Pbca, and R = 0.0540 for 3513 reflections. In both complexes, the centrosymmetric 18-crown-6 and guest molecules are joined together through the NH?O (crown) hydrogen bonds, which involve all the hydrogen atoms of the hydrazine group. The NH?O=C intramolecular hydrogen bond is observed in the guest molecule. In structure I, the water molecule serves as a bridge between the guest molecules related by the glide-reflection plane and combines the guest-host-guest complexes into layers. In structure II, the guest molecules are linked into chains through hydrogen bonds of the NH?O=C type; in turn, the chains composed of guest molecules and the crown ether molecules bonded to these chains form a layered structure.  相似文献   

11.
The structures of 1-benzoyl-3-(pyridin-2-yl)-thiocarbamide C13H11N3O1S1 (I) and 2-benzoylimino-1,2,4-thiadiazole[2,3-a]pyridine C13H9N3O1S1 (II) are studied by X-ray diffraction. Structures I [a = 5.342(4) Å, b = 20.428(5) Å, c = 11.784(4) Å, β = 90.55(2)°, Z = 4, space group P21/n) and II [a = 6.258(6) Å, b = 18.068(14) Å, c = 10.185(10) tA, β = 95.45(8)°, Z = 4, space group P21/n) are determined by direct methods and refined to R 1 = 0.0673 and 0.0802, respectively. In structure I, both intramolecular (involving the O atom) and intermolecular (involving the N and S atoms) hydrogen bonds are observed. The latter bonds are responsible for the formation of centrosymmetric molecular dimers. In structure II, a short intramolecular contact (2.168 Å) is observed between the S and O atoms.  相似文献   

12.
The crystal structures of Ca[Sb(Edta)]2 ? 8H2O (I) and Ba{ [Bi(Edta)]2H2O} ? H2O (II) are determined by X-ray diffraction. Crystals I are monoclinic, a = 7.132 Å, b = 21.906 Å, c = 10.896 Å, β = 91.13°, Z = 2, and space group P21/n. Crystals II are triclinic, a = 8.995 Å, b = 12.750 Å, c = 13.577 Å, α = 77.42°, β = 73.90°, γ = 86.53°, Z = 2, and space group $P\bar 1$ . In structure I, the coordination number of the antimony atom is 6 + LEP (lone electron pair), and the polyhedron is a ψ-pentagonal bipyramid with the lone electron pair at an equatorial position. In structure II, two crystallographically independent complexes Bi(Edta)? and the coordination water molecule form tetranuclear associates. The environments of two independent bismuth atoms (the coordination number is eight) are similar, and their polyhedra can be described as distorted dodecahedra. The effect of the lone electron pair on the structures of polyhedra of antimony and bismuth is discussed.  相似文献   

13.
Double zirconium and 3d-transition metal phosphates of the compositions M 0.5Zr2(PO4)3[M = Mn (I), Co (II), Ni (III), Cu (IV), Zn (V)] have been synthesized and the types of their structures have been refined. Compounds I, II, III, IV, and V are all monoclinic (sp. gr. P21/n, Z = 4) and have the unit cell parameters a = 12.390(3), 12.389(3), 12.385(3), 12.389(3), 12.389(2) Å; b = 8.931(4), 8.928(3), 8.924(4), 8.925(4), 8.929(3) Å; c = 8.843(3), 8.840(2), 8.840(3), 8.841(3), 8.842(2) Å, β = 90.55(1), 90.54(1), 90.53(1), 90.53(1), 90.54(1)°; V = 978.5, 977.7, 977.0, 977.4, 978.1 Å3, respectively. All the structures have the {[Zr2(PO4)3]?}3-type frameworks. The crystallographic data for 3d-transition and alkali earth metal phosphates described by the general formula M 0.5Zr2(PO4)3 are compared.  相似文献   

14.
The crystal structures (cubic system, sp. gr. Im3m) of solid solutions of oxygen in niobium of the Compositions NbO x<0.01 (I), NbO0.150(6) (II) and NbO0.107(5) (III) were studied for the first time by single-crystal X-ray diffraction analysis (Syntex P1 diffractometer, λMoKα radiation). Crystals I (a = 3.2969(8) Å) and II (a = 3.3082(6) Å) were prepared by the electrolysis of salt melts. Crystal III (a = 3.3114(4) Å) was obtained after partial dissolution of crystal I in a solution of HNO3, HCl, and HF resulting in its saturation with oxygen. The residual electron density maps for crystal I revealed no O atoms. Localization of the O atoms in the tetrahedral cavities of crystal II and in the tetrahedral and octahedral cavities of crystal III indicates that the arrangement of the interstitial positions of oxygen atoms depends on the procedure of preparing solid solutions. In crystals II and III, the amplitudes of thermal vibrations of the Nb atoms are smaller and the anharmonicity of these vibrations is higher than those in crystal I virtually devoid of oxygen. The reasons for the substantially higher oxygen content (up to 17 at. %) in cubic crystals of the solid solutions of O in Nb prepared by the electrolytic method than in the analogous phase obtained upon heating (lower than 7 at. %) are discussed.  相似文献   

15.
Hydroxocomplexonate K2[GaEdta(OH)] · 6H2O (I) and nitronium salts BH+GaEdta · 4H2O (II) and BH+AlEdta · 4H2O (IV) are synthesized from aqueous solutions at pH 8, 6, and 7, respectively. AlHEdta(H2O) (III) is isolated from an acid solution (pH 1.5). Structures I, II, and IV are determined by single-crystal X-ray diffraction. The X-ray powder diffraction analysis of III has revealed that its crystals are not isostructural with those of similar complexes of other metals. Crystals I–IV are monoclinic. The unit cell parameters are a = 10.482(1), 15.735(4), 5.768(4), and 15.756(4) Å; b = 10.442(2), 12.511(2), 14.884(11), and 12.453(3) Å; c = 19.590(4), 17.330(5), 19.113(12), and 17.328(6) Å; β = 101.30(2)°, 104.54(2)°, 90.74(5)°, and 104.75(2)° for I–IV, respectively.  相似文献   

16.
The structure of 3-(isonicotinoyl)-2-oxooxazolo[3,2-a]pyridine, C13H8N2O3, (I) is determined by X-ray powder diffraction analysis. Crystals I are orthorhombic, a = 16.610(2) Å, b = 3.853(1) Å, c = 16.431(2) Å, Z = 4, and space group Pna21. The structure is solved by the grid search procedure and refined by the Reitveld method (Rp = 0.086, Rwp = 0.115, Re = 0.030, and χ2 = 11.138). The structure of the product of hydrolysis of compound I, C12H10N2O2, (II) is determined by the single-crystal X-ray diffraction technique. Crystals II are orthorhombic, a = 8.755(4) Å, b = 10.526(17) Å, c = 23.088(6) Å, Z = 8, and space group Pc21b. The structure is solved by the direct method and refined by the full-matrix least-squares procedure to R = 0.0464. A fragment of two fused heterocycles in I is planar. The dihedral angle between the plane of the pyridine ring in the isonicotinoyl fragment and the plane of the bicyclic system is 51.2(2)°. Both exocyclic CO groups that are adjacent to the five-membered fragment contain double bonds. The structures of two crystallographically independent molecules II are almost identical to each other, and the isonicotinoyl fragment is nearly perpendicular to the plane of the pyridone fragment [84.3(1)° and 87.0(1)°].  相似文献   

17.
The molecular and crystal structures of chiral 1R,4S-2-(4-carbomethoxy)benzylidene-n-menthan-3-one (I) are determined by X-ray diffraction analysis. Crystals I are orthorhombic; at 20°C: a = 11.961(3) Å, b = 26.453(8) Å, c = 5.400(2) Å, space group P212121, and Z = 4 (C19H25O3). In molecule I, the cyclohexanone ring with the axial methyl and isopropyl substituents adopts a chair conformation. It is found that the enone and arylidene fragments of compound I have a substantially nonplanar structure. The shortened intramolecular contacts between atoms of the arylidene grouping and the α fragment of the cyclohexanone ring and their associated distortions of bond angles at the sp 2 carbon atoms are the common structural features of 2-arylidene-n-menthan-3-ones irrespective of the stereochemical configuration of the C(4) chiral center.  相似文献   

18.
The crystal structures of Ca9 R(VO4)7 (R = Nd (I), Sm (II), or Gd (III)) were studied by the Rietveld method. The compounds are isostructural to Ca3(VO4)2 and are crystallized in the trigonal system (sp. gr. R3c, Z = 6). The unit-cell parameters are as follows: for I, a = 10.8720(5) Å, c = 38.121(1) Å; for II, a = 10.8652(5) Å, c = 38.098(1) Å; and for III, a = 10.8631(5) Å, c = 38.072(1) Å. In the structures of I and II, the M(1), M(2), and M(3) positions are statistically occupied by the rare-earth cations and calcium anions. In the structure of III, the Gd3+ cations occupy the M(1) and M(2) positions. The distributions of the R 3+ cations over the positions are characteristic of each structure. The composition of the cerium-ontaining compound Ca9.81Ce0.42(VO4)7 (a = 10.8552(5) Å, c = 38.037(1) Å) was refined and its crystal structure was solved from the X-ray powder data. In this compound, cerium atoms are in the oxidation states +3 and +4.  相似文献   

19.
Crystals of [N-(2-aminoethyl)iminodiacetato](1,10-phenanthroline)copper(II) tetrahydrate, [Cu(Aeida)(Phen)] · 4H2O (I), are obtained, and their structure is determined. Crystals I are triclinic, and the unit cell parameters are as follows: a = 8.341(1) Å, b = 9.424(1) Å, c = 13.864(2) Å, α = 74.23(1)°, β = 79.25(1)°, γ = 82.67(1)°, Z = 2, and space group P1. The structural units of the crystal are [Cu(Aeida)(Phen)] molecular complexes and crystallization water molecules. The coordination polyhedron of the copper atom is a tetragonal bipyramid with four nitrogen atoms in the equatorial plane (mean Cu-N, 2.05 Å) and two oxygen atoms of the acetate groups in axial positions (Cu-O, 2.264 and 2.426 Å; O-Cu-O angle, 148.8°). The Aeida and Phen ligands fulfill the tetradentate (2N + 2O) chelate and bidentate (2N) chelate functions, respectively. The complexes are joined into dimer associates in which the interplanar spacing between Phen molecules is equal to 3.54 Å and the Cu?Cu distance is 7.02 Å.  相似文献   

20.
Crystals structures of two modifications of the copper(II) compound with racemic threonine Cu(D-Tre)(L-Tre) are determined by the electron diffraction technique. The unit cell parameters, space group, and number of formula units per unit cell for the crystals of two modifications are as follows: a = 11.10(3) Å b = 9.56(2) Å, c = 5.11(2) Å, γ = 92.6(2)°, space group P21/b, and Z = 2 (I); and a = 22.20(3) Å, b = 9.56(2) Å, c = 5.11(2) Å, γ = 92.6(2)°, space group C21/b, and Z = 4 (II). The structures are polytypic modifications of the same compound.  相似文献   

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