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1.
Two crystalline modifications (I and II) of the phenanthroline complex of europium nitrate with the same chemical composition, Eu(NO3)3(Phen)2, are synthesized under different conditions by varying the solvents, temperatures, and crystallization rates. The crystal structures of these modifications are determined using X-ray diffraction. Crystalline modifications I and II differ in the unit cell parameters and the positions of the complexes in the unit cell. The geometric characteristics of the complexes in the structures of compounds I and II differ insignificantly. Crystals of compound I belong to the isostructural family Ln(NO3)3(Phen)2 (Ln = La-Lu). Crystals of compound II (new phase) are studied for the first time. Crystals of I and II are monoclinic, space group C2/c, and Z = 4. The unit cell parameters are as follows: a = 11.1555(10) Å, b = 17.9698(10) Å, c = 13.0569(10) Å, β = 100.507(10)°, and V = 2572.1(3) Å3 for modification I and a = 9.5153(10) Å, b = 15.4546(10) Å, c = 17.1763(10) Å, β = 93.451(10)°, and V = 2521.3(3) Å3 for modification II. The difference between the molecular complexes in the structures of compounds I and II is revealed by the superposition method. Complexes II are arranged along the C 2 axis and are statistically disordered with respect to this axis.  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.
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   

4.
The title compound N-(4-acetyl-5,5-dimethyl-4,5-dihydro-1,3,4-thiadiazol-2-yl)acetamide (III) was obtained from the reaction of 2-(propan-2-ylidene)hydrazinecarbothioamide (II) with acetic anhydride instead of formation of the desired thiosemcarbazide derivative of Meldrum acid. The structures of II and III were established by elemental analysis, IR, NMR, Mass and X-ray crystallographic studies. II crystallizes in triclinic system, sp. gr. $P - \bar 1$ Z = 2; III crystallizes in the monoclinic system, sp. gr. P21/c, Z = 8. Density functional theory (DFT) calculations have been carried out for III. 1H and 13C NMR of III has been calculated and correlated with experimental results.  相似文献   

5.
The crystal structures of 1,4-benzothiazin-2(1H)one (C8H7SNO) (I) and 3-methyl-1,4-benzothiazin-2(1H)one (C9H9SNO) (II) have been determined by X-ray diffraction methods. I crystallizes in the monoclinic system with space group P21/n, while II crystallizes in triclinic with space group P $\bar 1$ . The molecular features in both the structures are almost similar; however, there exists an intermolecular interaction in (II) that could be due to the methyl group.  相似文献   

6.
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   

7.
Single crystals of acid salt hydrates M I{M II[H(XO4)2](H2O)2}, where M I, M II, and X are K, Zn, and S (I); K, Mn, and S (II); Cs, Mn, and S (III); or K, Mn, and Se (IV), respectively, were synthesized and studied by X-ray diffraction analysis. Compounds I–IV (space group $P\bar 1$ ) are isostructural to each other and to hydrate KMg[H(SO4)2](H2O)2 (V) studied earlier. Structures I–V, especially, the M I-O, M II-O, and X-O distances and the O?H?O (2.44–2.48 Å) and Ow-H?O (2.70–2.81 Å) hydrogen bonds, are discussed.  相似文献   

8.
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   

9.
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   

10.
The crystal structures of salicylideneguanylhydrazinium chloride hydrate hemiethanol solvate (I), salicylideneguanylhydrazinium trichloroaquacuprate(II) (II), and bis(salicylideneguanylhydrazino)cobalt(III) chloride trihydrate (III) are determined using X-ray diffraction. The structures of compounds I, II, and III are solved by direct methods and refined using the least-squares procedure in the anisotropic approximation for the non-hydrogen atoms to the final factors R = 0.0597, 0.0212, and 0.0283, respectively. In the structure of compound I, the monoprotonated molecules and chlorine ions linked by hydrogen bonds form layers aligned parallel to the (010) plane. In the structure of compound II, the salicylaldehyde guanylhydrazone cations and polymer chains consisting of trichloroaquacuprate(II) anions are joined by an extended three-dimensional network of hydrogen bonds. In the structure of compound III, the [Co(LH)2]+ cations, chloride ions, and molecules of crystallization water are linked together by a similar network.  相似文献   

11.
Thiosemicarbazide complexes of nickel(II) [Ni(TSC)2](HSal)2 (I) and copper(II) [Cu(TSC)2](HSal)2 (Ia) (TSC is thiosemicarbazide and HSal is a salycilate anion), as well as complexes [Ni(TSC)2](SO4) · 2H2O (II) and [Ni(TSC)3]Cl2 · H2O (III), are synthesized and characterized by IR spectroscopy and X-ray diffraction. Monoclinic crystals I and Ia are isostructural; space group P21/n, Z = 2. Crystals II are monoclinic, space group P21/m, Z = 2. Crystals III are orthorhombic, space group Pbca, Z = 8. In I and Ia, two planar salycilate anions sandwich a planar centrosymmetric [Ni(TSC)2]2+ cation to form a supermolecule. The cation and anions are additionally bound by hydrogen bonds. Other hydrogen bonds connect supermolecules into planar layers. In structure II, centrosymmetric [Ni(TSC)2]2+ cations are connected by ??-stacking interactions into supramolecular ensembles of a specific type. The ensembles, water molecules, and (SO4)2? anions are bound in the crystal via hydrogen bonds. In the [Ni(TSC)3]2+ cation of structure III, ligands coordinate the Ni atom by the bidentate chelate pattern with the formation of five-membered metallocycles. These metallocycles have an envelope conformation unlike those in I and II, which are planar. In III (unlike in analogous complexes), a meridional isomer of the coordination octahedron of the Ni atom is formed. Together with Cl1? and Cl2? anions, cations form supermolecules, which are packed into planar layers with a square-cellular structure. The layers are linked by hydrogen bonds formed by crystallization water molecules that are located between the layers.  相似文献   

12.
13.
The crystal structures of bis{2,4-dibromo-6-[(2-hydroxyethylamino)-methyl]phenolato}copper (I), bis{2,4-dichloro-6-[(2-hydroxyethylamino)-methyl]phenolato}copper (II), and bis{2-[(2-hydroxyethylamino)-methyl]-4,6-dinitrophenolato}copper (III) in which the metal atom is located at the center of symmetry are determined using X-ray diffraction. Crystals of compounds I and II are isostructural. The copper atom in the structures of compounds I and I coordinates two singly deprotonated bidentate molecules of the ligand through the phenol oxygen atoms and the azomethine nitrogen atoms with the formation of a distorted planar square. In the crystals, complexes I and II form one-dimensional infinite chains along the b axis. In the structure of compound III, the coordination polyhedron of the central atom is an elongated tetragonal bipyramid with the base formed by the azomethine nitrogen atoms and the phenol oxygen atoms. Both vertices of the bipyramid are occupied by the oxygen atoms of the amino alcohol groups of the neighboring complexes, which are related to the initial complex through the center of symmetry. In turn, the oxygen atoms of the alcohol groups of the initial complex are located at the vertices of the coordination bipyramids of the metal atoms of the neighboring centrosymmetric complexes, thus forming infinite polymer chains along the a axis.  相似文献   

14.
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   

15.
The crystal structures of [Cd(H2 Edta)(H2O)] · 2H2O (I) and [Mn(H2O)4][Mn(HEdta)(H2O)]2 · 4H2O (II) are studied by X-ray diffraction [R 1 = 0.0209 (0.0272), wR 2 = 0.0571 (0.0730) for 2551 (4025) reflections with I > 2σ(I) in I (II), respectively]. Structure I contains mononuclear [Cd(H2 Edta)(H2O)] complexes with the C 2 symmetry, and structure II contains centrosymmetric trinuclear [Mn(H2O)4][Mn(HEdta)(H2O)]2 complexes. In I and II, the protonated ligands are hexadentate (2N + 4O), and the water molecule increases the coordination number of the metal atom to seven. The acid protons participate in short intermolecular hydrogen bonds, which are symmetric in II and asymmetric in I.  相似文献   

16.
The crystal structures of {4-bromo-2-[(2-hydroxyethylimino)-methyl]phenolo}aquacopper(II) nitrate hemihydrate (I), chloro-{4-bromo-2-[(2-hydroxyethylimino)-methyl]phenolo}copper hemihydrate (II), and chloro-{4-bromo-2-[(2-hydroxyethylimino)-methyl]phenolo}aquanickel (III) are determined using X-ray diffraction. Crystals of compound I are formed by cationic complexes, nitrate ions, and solvate water molecules. In the cation, the copper atom coordinates the singly deprotonated molecule of tridentate azomethine and the water molecule. The copper complexes are joined into centrosymmetric dimers by the O w -H···O hydrogen bonds. The crystal structure of compound II is composed of binuclear copper complexes and solvate water molecules. The copper atom coordinates the O,N,O ligand molecule and the chlorine ion, which fulfills a bridging function. The coordination polyhedron of the metal atom is a distorted tetragonal bipyramid in which the vertex is occupied by the chlorine atom of the neighboring complex in the dimer. Compound III is a centrosymmetric dimer complex. The coordination polyhedra of two nickel atoms related via the inversion center are distorted octahedra shared by the edge.  相似文献   

17.
Crystalline hydrogen selenate-phosphates M 2H3(SeO4)(PO4) [M = Rb (I) or K (II)] and M 4H5(SeO4)3(PO4) [M = K (III) or Na (IV)] were obtained by reactions of Rb, K, and Na carbonates with mixtures of selenic and phosphoric acid solutions. The X-ray structure study of single crystals revealed that I and II are isostructural (sp. gr. Pn). In these structures, SeO4 and H3PO4 tetrahedra are linked by hydrogen bonds to form corrugated layers. Structures III and IV (sp. gr. $P\bar 1$ ) have similar arrangements of non-hydrogen atoms but different hydrogen-bond systems. In III = K4(HSeO4)2{H[H(Se,P)O4]2}, the HSeO4 groups branch from the infinite anionic {H[H(Se,P)O4]2} chains. In IV = Na4[H(SeO4)2]{H[H1.5(Se, P)O4]2}, the anionic {H[H1.5(Se,P)O4]2} chains are crosslinked by hydrogen bonds formed by the [H(SeO4)2] dimers.  相似文献   

18.
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   

19.
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   

20.
The crystal structures of the 1: 1 and 1: 2 complexes between dibenzenehemiporphyrazine (I) and dimethylformamide (compounds II and III, respectively) are determined by X-ray diffraction. In both compounds, the macrocycle has a saddlelike shape. In III, the conformation of the macrocycle approximates the C 2v symmetry, which agrees closely with the results of quantum-chemical calculations for isolated molecule I and complex II. The ring conformation in crystal II is distorted under the effect of intermolecular interactions, as is evidenced by short intermolecular contacts. The complexes are stabilized by intermolecular N-H?O and C-H?O hydrogen bonds between the hydrogen atoms situated inside the cavity of the macrocycle and the oxygen atoms of the dimethylformamide molecules.  相似文献   

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