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1.
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   

2.
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   

3.
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   

4.
-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   

5.
Crystal structures of the compounds Ca9 R(VO4)7 (R = Tb (I), Dy (II), Ho (III), and Y (IV) have been studied by the method of the full-profile analysis. All the compounds are crystallized in the trigonal system (sp. gr. R 3 c, Z = 6) with the unit-cell parameters (I) a = 10.8592(1), c = 38.035(1), V = 3884.2(2) Å3; (II) a = 10.8564(1), c = 38.009(1) Å, V = 3879.6(2) Å3, (III) a = 10.8565(1) and c = 37.995(1) Å, V = 3878.3(2) Å3, and (IV) a = 10.8588(1), c = 37.995(1) Å, V = 3879.9(2) Å3. In structures I–IV, rare earth and calcium cations occupy three positions—M(1), M(2), and M(5). Rare earth cations occupy the R 3+ positions almost in the same way: 2.7–2.6(2) cations in the M(1) position; 2.7–2.3(2) cations in the M(2) position, and 0.6–1.0(1) cation in the M(5) position. At the same time, the occupancy of the M(5) position regularly increases with a decrease of the R 3+ radius.  相似文献   

6.
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   

7.
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   

8.
The synthesis of a series of ruthenium complexes with cyclothioether ligands is reported. The compounds were characterized by X-ray diffraction techniques. The molecular structures of [CpRu(PPh3)2(pms)]BF4 (1), [CpRu(PPh3)2(1,3-dithiane)]OTfl (2), [CpRu(PPh3)2(1,3,5-trithiane)]OTfl (3), and [CpRu(PPh3)(1,4-dithiane)]BF4 (4) show chelation occurs only when the sulfur atoms are separated by at least two C atoms, creating a ligand bite size large enough to chelate. Cell parameters: 1, space group P21/c, a = 14.601(4), b = 19.102(10), c = 14.751(7) Å, β = 98.28(3); 2, space group P21/c, a = 12.859(7), b = 15.576(3), c = 22.126(11) Å, β = 102.22(4); 3, space group P21/c, a = 12.7320(20), b = 15.571(5), c = 22.287(4) Å, β = 101.812(14); 4, space group Pbca, a = 11.2010(10), b = 16.321(7), c = 28.966(4) Å. Compounds 2 and 3 are X-ray isomorphous. The Ru–S bond lengths range from 2.341(3), 2.365(3) Å in compound 4 to 2.382(4) Å in compound 2. Upon chelation (compound 4), with subsequent loss of PPh3, the Ru–P bond shortens to 2.327(3) Å. This may be due to reduced steric hindrance about the Ru atom. No evidence for C–S bond lengthening is observed.  相似文献   

9.
Dimethyl 3-(p-chlorobenzoyl)-5-chloroindolizine-1,2-dicarboxylate, C19H13Cl2NO5, (2) and the product of its cyclization 1,2-bis(carbomethoxy)-6-chloro-3H-isoquinolino[1,2,3-d,c]indolizine-3-one, C19H12ClNO5, (3) are synthesized, and their molecular and crystal structures are determined by the single-crystal X-ray diffraction technique. Crystals 2 are monoclinic, a = 9.627(3) Å, b = 6.646(2) Å, c = 28.500(9) Å, β = 98.72(2)°, Z = 4, and space group P21/c. Crystals 3 are monoclinic, a = 7.048(4) Å, b = 10.582(4) Å, c = 21.760(7) Å, β = 97.23(4)°, Z = 4, and space group P21/c. The structures are solved by the direct method and refined in the anisotropic approximation by the full-matrix least-squares procedure to R = 0.0504 and 0.0510 for 2 and 3, respectively. In both structures, the intramolecular and intermolecular contacts involving the C, H, and O atoms are observed.  相似文献   

10.
The molecular and crystal structures of chiral 1R, 4R-cis-2-(4-hydroxybenzylidene)-p-menthan-3-one (I) are determined by X-ray diffraction analysis. Single crystals of I are orthorhombic, a = 8.997(2) Å, b = 11.314(2) Å, c = 14.847(3) Å, V = 1511.3(5) Å3, Z = 4, and space group P212121. The cyclohexanone ring in molecules of compound I has a chair-type conformation with the axial methyl and equatorial isopropyl groups. The enone and benzylidene groupings are nonplanar. The considerable distortion of bond angles at the sp 2 carbon atoms of the benzylidene grouping and the puckering parameters of the cyclohexanone ring in the structure of I are close to those observed for the previously studied compound with the p-methoxy substituent. In the crystal, molecules I are linked by very short intermolecular hydrogen bonds .  相似文献   

11.
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   

12.
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   

13.
The synthesis, variable temperature NMR spectra, and crystal structures of two crystalline forms, 2a and 2b, of the enamine 1-(N,N-diethylamino)-2,2-bis(2-nitrophenylthio)ethene have been obtained. Both forms crystallize in the monoclinic space group P21/a. The two phases have similar molecular structures but possess different intermolecular C–H······O hydrogen bonding interactions. Both forms exhibit disorder within the NEt2 fragment at 298 K: sufficient disorder persisted with 2a (orange needles) down to 100 K to make the geometric parameters pertaining to the enamine fragment unreliable. The disorder was effectively eliminated on cooling 2b down (red colored blocks) to 150 K. Cell dimensions for the 2a-phase are at 100 K: a = 11.1030(4) Å, b = 15.1325(7) Å, c = 12.4504(7) Å, β = 114.606(3)°, while for the 2b-phase at 150 K, a = 15.5206(4) Å, b = 7.6958(2) Å, c = 15.7137(3) Å, β = 92.580(7)°. The C–N bond length in the β-form at 150 K of 1.335(3) Å indicates considerable double bond character: the rotational barrier of the C–N bond in CDCl3 was calculated to be 52.4 kJ mol?1.  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.
Five derivatives of curcumin analogue (R = OCH2CH3 (1), R = N(CH3)2 (2), R = 2,4,5-OCH3 (3), R = 2,4,6-OCH3 (4), and R = 3,4,5-OCH3 (5)) were synthesized and characterized by 1H NMR, FT-IR and UV–Vis spectroscopy. The synthesized derivatives were screened for antityrosinase activity, and found that 4 and 5 possess such activity. The crystal structure of 1 was determined by single crystal X-ray diffraction: monoclinic, sp. gr. P21/c, a = 17.5728(15) Å, b = 5.9121(5) Å, c = 19.8269(13) Å, β = 121.155(5)°, Z = 4. The molecule 1 is twisted with the dihedral angle between two phenyl rings being 15.68(10)°. In the crystal packing, the molecules 1 are linked into chains by C?H···π interactions and further stacked by π···π interactions with the centroid–centroid distance of 3.9311(13) Å.  相似文献   

16.
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   

17.
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   

18.
The single-crystal structures of two aminodienes containing an oxazole fragment, namely, 1-pip-eridyl-4-[5-(4-nitrophenyl)-oxazol-2-yl]-buta-1,3-diene C 18 H 19 N 3 O 3 (IIa) and 1-hexamethyleneimine-4-[5-(4-nitrophenyl)-oxazol-2-yl]-buta-1,3-diene C19H21N3O3 (IIb), are studied by X-ray diffraction. Structures IIa [a = 16.181(6) Å, b = 5.939(3) Å, c = 17.337(9) Å, β = 96.13(2)°, Z = 4, and space group P21] and IIb [a = 7.4704(11) Å, b = 10.9904(19) Å, c = 43.434(6) Å, β = 91.24(1)°, Z = 8, and space group P21/c] are solved by the direct method and refined to R = 0.060 and 0.238, respectively. Although the ring sizes of the cyclic amines in compounds IIa and IIb are different, the designs of two structures are identical. Each structure contains two topologically identical but crystallographically independent molecules. In structure IIa, the intramolecular hydrogen bonds between the N atoms of the oxazole fragments and the H atoms of the diene fragments are formed. In structure IIb, similar bonds are absent.  相似文献   

19.
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   

20.
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   

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