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991.
Reactions of SmI2 in THF with ArSSAr produced two binuclear samarium thiolate complexes [(THF)3I2- Sm(μ-SAr)]2 [Ar=Ph (1), 4-Me2NC6H4 (2)] in high yields. The structure of 2 was characterized by single crystal X-ray crystallography. The crystal of 2 belongs to the triclinic system with space group P 1 and a=0.95705(13) nm, b= 1.22287(14) nm, c= 1.26450(14) nm, a=64.194(11)°, B=78.491(13)°, y=76.176(12)°, V= 1.2860(3) nm^3, Z= 1,μ=4.783 mm^-1, Dc= 1.964 Mg/m^3, M= 1521.19, S= 1.046, R1=0.0358, wR2=0.0910. X-ray analysis revealed that 2 is a thiolate-bridged dimer in which each Sm atom adopts a distorted pentagonal bipyramidal coordi- nation geometry. 相似文献
992.
E. V. Alekseev E. V. Suleimanov E. V. Chuprunov G. K. Fukin L. G. Alekseeva 《Journal of Structural Chemistry》2005,46(5):936-940
The crystal structure of KAsUO6·3H2O was solved at 100 K and 293 K. KAsUO6·3H2O at T = 100 K: tetragonal, P4/ncc, a = 7.2037(6) Å, c = 17.811(2) Å; Z = 4, R1 = 0.0263, wR2 = 0.0546, for 618 independent reflections; at T = 293 K: tetragonal, P4/ncc, a = 7.1600(4) Å, c = 17.746(1) Å; Z = 4, R1 = 0.0263, wR2 = 0.0433 for 427 independent reflections. The results of X-ray analysis are compared with our previous data on heat capacity of this compound, and changes that take place in the structure at elevated temperature are considered. 相似文献
993.
The title complex has been synthesized by the reaction of silicotungstic acid, 1,10-phenanthroline (phen) monohydrate and cupric acetate. The crystal structure belongs to triclinic system, space group P1 with a=1.158 46(15) nm, b=1.658 8(2) nm, c=1.664 4(2) nm, α=82.090(2)°, β=76.001(2)°, γ=86.531(2)°, and V=3.072 6(7) nm3, Dc=3.887 g·cm-3, Z=2, F(000)=3 196. R1=0.086 7, wR2=0.185 8. The structure shows that the copper(Ⅱ) atom is coordinated with two nitrogen atoms from the one phen and three oxgygen atoms from three water, forming a distorted square-pyramid configuration The cyclic voltametric behavior of the complex is also reported. CCDC: 298807. 相似文献
994.
O. G. Shakirova D. Yu. Naumov Yu. G. Shvedenkov N. I. Alferova G. V. Dolgushin L. G. Lavrenova 《Journal of Structural Chemistry》2003,44(4):642-649
A new trinuclear nickel(II) complex with 4-(pyridyl-2)-1,2,4-triazole (pytrz), [Ni3(pytrz)6(H2O)6](NO3)6, has been synthesized, and its crystal structure has been determined. The compound was studied by X-ray phase analysis (XRPA), magnetochemical measurements, and electronic and IR spectroscopy. 相似文献
995.
Robin D. Rogers Philip D. Richards 《Journal of inclusion phenomena and macrocyclic chemistry》1987,5(5):631-638
The title complex was crystallized from a saturated solution of 18-crown-6 in nitromethane at 5°C and cooled to –150°C prior to X-ray diffraction data collection. At –150° C 18-crown-6·2(CH3NO2) is monoclinic,P21/n witha=9.290(2),b=7.864(6),c=13.627(8) Å, =1000.84(4)° andD
calc=1.31 g cm–3 for Z=2. Leastsquares refinement using 1521 independent observed reflections [F
o5(F
o)] led to a final conventionalR value of 0.041. The complex at –150°C is isostructural with its room temperature structure with the exception of the orientation of the methyl hydrogen atoms and their crown ether oxygen interactions. The methyl group hydrogen atoms were fully refined isotropically. The crown ether resides around a center of inversion and hasD
3d symmetry. There is one methyl hydrogen...crown interaction at 2.35(3) Å, one apparently bifurcated hydrogen bond utilizing a second methyl hydrogen atom (2.55(3), 2.65(3) Å) and the third hydrogen atom is actually directed away from the crown ring (closest H...O contact=2.67(3) Å).
Supplementary Data relating to this article are deposited with the British Library as Supplementary Publication No. SUP 82048 (5 pages).For part 2, see reference [24]. 相似文献
996.
Dehydrofluorination ofO-(-hydroperfluoroisobutyl)acetone oxime affords 2,2-bis(tri-fluoromethyl)-5-methyl-4-pyrrolin-3-one; the molecular structure of the latter was unambiguously established by X-ray diffraction method.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 951–953, May, 1994. 相似文献
997.
New Complexes of the Lanthanoides with Bidentate Ligands. The Crystal Structures of [(C17H17N2)GdBr2(thf)2] and [(C17H17N2)3Ln] (L = Sm, Gd) Reaction of [(AIP)Li] with GdBr3 leads to a new mononuclear complex [(AIP)GdBr2(thf)2] 1 . In contrast to this with SmI2 the compound [(AIP)3Sm] 2 is build up. Such complexes are also formed with Gd(OR*)3 (R* = OtBu2C6H3) and [(AIP)Li] in a 1:3 ratio, [(AIP)3Gd] 3 . The structures of 1–3 were characterized by X-ray single crystal structure analysis ( 1 : space group Pna21 (No. 33), Z = 4, a = 1 972.7(9) pm, b = 984.7(5) pm, c = 1 425.0(8) pm, α = β = γ = 90°; 2 · 2 THF: space group C2/c (No. 15), Z = 8, a = 3 644.4(9) pm, b = 1 437.5(5) pm, c = 2 334.4(7) pm, β = 1 21.07(6)°; 3 : space group P2(1)/c (No. 14), Z = 4, a = 1 872.9(1) pm, b = 1 064.6(1) pm, c = 2 282.4(2) pm, β = 103.75(8)°). 相似文献
998.
Single Crystals of A? Nd2S3, U? Ho2S3, D? Er2S3, and E? Lu2S3 through the Oxidation of Reduced Lanthanide Chlorides with Sulfur The oxidation of reduced chlorides (MCl2) or chloridehydrides (MClHx) of the lanthanides with sulfur (850°C, 7 d, tantalum ampoule) usually results in the formation of their sesquisulfides (M2S3) as the main product. In the presence of appropriate fluxes (e. g., NaCl), they often are obtained as single crystals, and the flux appears to decide which modification is favourized. Single crystals of Nd2S3 , (from NdCl2 + NaCl + S, 2 : 2 : 1, A-type: orthorhombic, Pnma (no. 62), Z = 4; a = 743.97(5), b = 402.78(3), c = 1551.96(9) pm, Vm = 70.015(8) cm3/mol, R , = 0.026, Rw = 0.023), Ho2S3 , (from Na0.25HoClH0.75 + S, 8 : 9, U type: orthorhombic, Pnma (no. 62), Z = 4, a = 1057.24(7), b = 384.48(4), c = 1041.15(7) pm, Vm = 63.716(9) cm3/mol, R , = 0.023, Rw = 0.020), Er2S3 , (from ErClH0.67 + NaCl + S, 2 : 2 : 1, D type: monoclinic, P21/m (no. 11), Z = 6, a = 1744.18(9), b = 398.22(3), c = 1010.13(6) pm, β = 98.688(4)°, Vm = 69.610(7) cm3/mol, R = 0.031, Rw = 0.029) and Lu2S3 , (from LuClH0.67 + NaCl + S, 2 : 2 : 1, E type: trigonal, R3 c (no. 167), Z = 6, a = 672.86(2), c = 1816.84(9) pm, c/a = 2.70, Vm = 71.497(6) cm3/mol, R = 0.023, Rw = 0.020) as well as more systematic general investigations (syntheses of the lanthanide sesquisulfides from the elements in the presence of NaCl as a flux in sealed tantalum containers at 850°C) are the main topic of the work presented here. 相似文献
999.
Kazuyoshi Yano Hiroshi Yoshitake Uwe T. Bornscheuer Rolf D. Schmid Kazunori Ikebukuro Kenji Yokoyama Yuzo Masuda Isao Karube 《Analytica chimica acta》1997,340(1-3):41-48
Piezoelectric quartz crystal sensors were developed using lipids with various properties for highly sensitive detection of chemical vapors. Lipids with varying lengths of alkyl chains were coated onto 10 MHz AT-cut quartz crystal resonators and the response of these modified crystals to chemical vapors were measured. It was shown that hydrophilic compounds, such as ethanol and methanol, could be recognized efficiently by lipids having shorter alkyl chains, whereas lipids with longer alkyl chains showed affinity to more hydrophobic vapors, such as toluene, hexane and cyclohexane. Frequency changes caused by adsorption of alcohols could be enhanced when cholesterol was co-immobilized in the lipid layer. To confirm the assumption that the sensor-response might be affected by the properties of lipids derived from acyl chains, we have examined the effects of two types of newly synthesized unusual lipids on sensor response. When lipids having one triple bond each at different positions on their alkyl chains were coated onto quartz crystals separately, lower responses were observed compared to responses obtained for a sensor with immobilized, saturated phosphatidylcholine. Lipids containing -branched acyl chains, however, showed good affinity for organic vapors, and sensor responses improved 4–5-fold. Moreover, these sensors were shown to have sensitivity of the same order as the humans' sense of smell (10−5–10−6 w/w in liquid paraffin) when measured using standard odorants (isovaleric acid, skatole, etc.) for an olfactometry established in Japan. 相似文献
1000.
Photocycloadditionof(4-methyl-7-coumarinyl)OxyaceticAcidPropanediolDiesterandX-rayCrystalStructureofProductDuDa-Ming;WangYong... 相似文献