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1.
Two novel heterometallic cubane-like and double cubane-like clusters, {MoCu3S3(S2COEt)}(O)(Ph3P)3 I and {Mo2Cu6S6(SCMe3)2}(O)2(Ph3P)4 II, were synthesized by reaction of {MoCu2S3}(O)(Ph3P)3 with CuS2COEt and CuSCMe3, respectively. ClusterI crystallized in the triclinic space group (2) witha=12.766(6) Å,b=22.904(5) Å,c=10.522(3) Å, =99.86(2)°, =109.68(2)°, =86.84(3)°,V=2854(2) Å3,Z=2,R=0.049 for 6622 observed reflections (I>5(I)) and 410 variables. ClusterII crystallized in the triclinic space group (2) with dimensionsa=14.212(4) Å,b=14.725(5) Å,c=12.396(8) Å, =110.32(4)°, =90.40(5)°, =62.88(2)°,V=2129(2) Å3,Z=1,R=0.039 for 6020 observed reflections (I>3(I)) and 461 variables. ClusterI consists of a neutral cubane-like molecule with the core {MoCu3S3(S2COEt)}2+, in which one corner of the cubane-like core is a novel triply bridging bidentate 1,1-dithiolato (xanthate, S2COEt) ligand. ClusterII is a double cubane-like one, in which two cubane-like cores {MoCu3S3(SCMe3)}2+ are connected by two Cu-S bonds of the triply bridging monothiolato (SCMe 3 ) ligand. Two different pathways of unit construction from a small heterometallic cluster {MoCu2S3}(O)(Ph3P)3 have been outlined. Comparisons of the selected bond lengths and bond angles for the cubane-like core {MoCu3S3 X} (X=Cl, Br, S2COEt, SCMe 3 ) are given. Spectroscopic properties of the title clusters are also reported.  相似文献   

2.
Crystals of PbCu3(OH)(NO3)(SeO3)3·1/2H2O [a=7.761(3)Å,b=9.478(4)Å,c=9.514(4)Å, =66.94(2)°, =69.83(2)°, =81.83(2)°, space group P ,Z=2] and Pb2Cu3O2(NO3)2(SeO3)2 [a=5.884(2)Å,b=12.186(3)Å,c=19.371(4)Å, space group Cmc21,Z=4] were synthesized under hydrothermal conditions. Their crystal structures were refined with three-dimensional X-ray data toR w=0.033 resp. 0.055. In PbCu3(OH)(NO3)(SeO3)3·1/2H2O the Cu atoms are [4+1] and [4+2] coordinated and via SeO3 groups a three-dimensional atomic arrangement is built up. In Pb2Cu3O2(NO3)2(SeO3)2 there are sheets, which are connected only via Pb-O bonds ranging from 2.98 Å to 3.16 Å.
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3.
Summary The mixed phosphine-phosphine oxides Ph2P(CH2)n-P(O)Ph2 (n = 1 or 2) react with K2PtCl4 to give cis-{PtCl2- 1-Ph2P(CH2) n P(O)Ph2]2}. Treatment of the latter (n = 2) with transition metal chlorides MCl2·nH2O, or with Me2SnCl2, SnCl4·5H2O, Th(NO3)4·xH2O or UO2(NO3)2· 6H2O, gives novel heterobimetallic complexes identified as cis-{PtCl2[-Ph2P(CH2)2P(O)Ph2]2MX2}·nH2O. Attempts to prepare similar heterobimetallic complexes using the starting complexes {PtX2[ 1-Ph2PCH2P(O)-Ph2]2} (X = C1), cis- or CN, trans-] were unsuccessful. Possible reasons for this are discussed.  相似文献   

4.
The crystal structure of the new phase Cu7(OH)6(TeO3)2(SO4)2 [a=7.389 (1),b=7.638 (1),c=7.662 (2) Å, =75.17 (1), =75.90 (1), =84.19 (1)°;Z=1] was determined by direct methods andFourier summations from X-ray intensities, and was refined in space group P -C i 1 toR=0.039. As usual, the Cu(II) atoms are coordinated to four O atoms forming approximately a square with average Cu-O=1.96 (3) Å; one or two more distant O neighbours complete the coordination. The shape of the TeO3 group is a rather clear-cut trigonal pyramid. A disorder was found for the SO4 tetrahedra. The compound was synthesized under hydrothermal conditions [500 (10) K, saturation vapour pressure].
Herrn Prof. Dr.K. Komarek zum 60. Geburtstag gewidmet.  相似文献   

5.
Two novel substituted amidino-benzothiazoles 6-(N-isopropyl)amidino-2-methylbenzothiazole 4 and 2-amino-6-(N-isopropyl)amidinobenzothiazole 6 were prepared in multistep synthesis in form of hydrochloride salts. They were characterized by means of IR, 1H, and 13C-NMR spectroscopy and elemental analysis. The crystal structures have been also determined by X-ray analysis. Both compounds crystallize as colorless prisms in the triclinic crystal system, space group P . Crystal data: (4) a = 8.741(4) Å, b = 9.602(7) Å, c = 9.946(2) Å, = 63.94(3)°, = 79.18(2)°, = 79.68(3)°, V = 732.1(6) Å3, Z = R = 0.0396; a = 8.106(1) Å, b = 9.148(2) Å, c = 9.291(2) Å, = 104.83(1)°, = 103.36(2)°, = 90.62(1)°, V = 646.2(2) Å3 , Z = 2, R = 0.0376. The bond distances and angles in both structures are almost similar. Between these two structures was found the difference in the orientation of the 6-(N-isopropyl)amidino moiety with respect to the benzothiazole ring. In the crystal structures of the both compounds the intermolecular hydrogen bonds form three-dimensional networks.  相似文献   

6.
Summary From a survey of spectroscopic and structural data of six corresponding 2-hydroxybenzamides and 2-hydroxythiobenzamides (amide, N-methylamide, N,N-dimethylamide, piperidide, morpholide, 2,6-dimethylpiperidide) remarkable similarities between O(N)-H ... O and O(N)-H ... S hydrogen-bonds are obtained, concerning both, hydrogen-bond patterns and hydrogen-bond strengths. In dilute solution the OH groups of all compounds are intramolecularly associated to the (thio)carbonyl O (S) atoms with distinctly larger hydrogen-bond strengths for primary and secondary amides [ (O-H)=2950–3020 cm–1, (OH)=12.16–11.99 ppm] and thioamides [ (O-H)=2960–3000 cm–1, (OH)=11.65–11.13 ppm], than for tertiary amides [ (O-H)=3200–3250 cm–1, (OH)=9.95–8.95 ppm] and thioamides [ (O-H)=3245–3330 cm–1, (OH)=8.09–7.06 ppm]. In the solid state, the OH groups of the primary and secondary (thio)amides are also engaged in rather strong intramolecular O-H ... O=C [O ... O=2.51 Å, (O-H)=2700–2750 cm–1] and O-H ... S=C [O ... S=2.90–2.94 Å, (O-H)=2700–2840 cm–1] hydrogen-bonds; thetrans-NH groups of the primary (thio)amides and the NH groups of the secondary (thio)amides connect the molecules to N-H ... O-H [N ... O=2.93–3.10 Å, (N-H)=3319–3407 cm–1] hydrogen-bonded chains; the remainingcis-NH groups of the primary (thio)amides give rise to eight-membered cyclic dimers via N-H ... O=C [N ... O=2.93 Å, (N-H)=3226 cm–1] and N-H ... S=C [N ... S=3.46–3.47 Å, (N-H)=3233–3277 cm–1] hydrogen-bonds. Contrary, the OH groups of the tertiary (thio)amides are intermolecular associated in the solid state and link the molecules to O-H ... O=C [O ... O=2.63–2.75 Å, (O-H)=3075–3135 cm–1] and O-H ... S=C [O ... S=3.18–3.26 Å, (O-H)=3130–3190 cm–1] hydrogen-bonded chains.
O-H ... O(S)-Wasserstoffbrückenbindungen in 2-Hydroxy(thio)benzamiden. Ein Überblick über spektroskopische und strukturelle Daten
Zusammenfassung Aus einer Zusammenstellung von spektroskopischen und strukturellen Daten von sechs entsprechenden 2-Hydroxybenzamiden und 2-Hydroxythiobenzamiden (Amid, N-Methylamid, N,N-Dimethylamid, Piperidid, Morpholid, 2,6-Dimethylpiperidid) ergeben sich bemerkenswerte Analogien zwischen O(N)-H ... O und O(N)-H ... S H-Brücken, die sowohl die H-Brücken-Muster als auch die H-Brücken-Stärken betreffen. In verdünnter Lösung sind die OH-Gruppen aller Verbindungen intramolekular mit den O(S)-Atomen der (Thio)Carbonylgruppen assoziiert, wobei die H-Brücken bei den primären und sekundären Amiden [ (O-H)=2950–3020 cm–1, (OH)=12.16–11.99 ppm] und Thioamiden [ (O-H)=2960–3060 cm–1, (OH)=11.65–11.13 ppm] deutlich stärker sind, als bei den tertiären Amiden [ (O-H)=3200–3250 cm–1, (OH)=9.95–8.95 ppm] und Thioamiden [ (O-H)=3245–3330 cm–1, (OH)=8.09–7.06 ppm]. Im Festkörper weisen die primären und sekundären (Thio)Amide ebenfalls sehr starke intramolekulare O-H ... O=C [O ... O=2.51 Å, (O-H)=2700–2750 cm–1] und O-H ... S=C [O ... S=2.90–2.94 Å, (O-H)=2700–2840 cm–1] H-Brücken auf; dietrans-NH-Gruppen der primären (Thio)Amide und die NH-Gruppen der sekundären (Thio)Amide verknüpfen die Moleküle über N-H ... O-H H-Brücken [N ... O=2.93–3.10 Å, (N-H)=3318–3407 cm–1] zu Ketten; die verbleibendencis-NH-Gruppen der primären (Thio)Amide bilden zyklische, über N-H ... O=C [N ... O=2.93 Å, (N-H)=3226 cm–1] und N-H ... S=C [N ... S=3.46–3.47 Å, (N-H)=3233–3277 cm–1] H-Brücken gebundene, 8-Ring-Dimere. Im Gegensatz dazu sind die OH-Gruppen der tertiären (Thio)Amide im Festkörper intermolekular assoziiert und verknüpfen die Moleküle über O-H ... O=C [O ... O=2.63–2.75 Å, (O-H)=3075–3135 cm–1] und O-H ... S=C [O ... S=3.18–3.26 Å, (O-H)=3130–3190 cm–1] H-Brücken zu Ketten.
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7.
Isostructural crystals of aluminum hexamolybdenocobaltate(III) and hexamolybdenocromate(III) Al[MMo6O18(OH)6] · 16H2O (M = Co(III) and Cr(III)) were studied using X-ray diffraction analysis. These compounds crystallize in the triclinic system: space group P , Z = 1, (calcd) = 2.665 and 2.611 g/cm3, respectively. The unit cell parameters were determined: for aluminum hexamolybdenocobaltate(III), a = 6.796(1) Å, b= 11.248(2) Å, c = 11.568(2) Å; = 101.36(2)°, = 96.95(2)°, = 102.23(2)°; for aluminum hexamolybdenocromate(III), a = 6.838(1) Å, b = 11.312(2) Å, c = 11.605(2) Å; = 101.29(3)°, = 97.13(3)°, = 102.15(3)°.  相似文献   

8.
The preparation, magnetic properties, and crystal structure of [(salen)Cu]4[(salen)Fe(H2O)2]2(ClO4)2 via hydrogen bonding are described [salen=N,N-ethylenebis (salicylideneiminate)]. Crystals are triclinic, of space group , with cell constants a=12.853(3), b=13.921(3), c=14.251(3) Å, =68.68(3)°, =87.86(3)°, =86.82(3)°, and Z=1. The structure was solved and refined to R=0.064 and R=0.068. The structure comprises the hexanuclear units which result from the linking of four mononuclear fragments [(salen)Cu] and two mononuclear fragment [(salen)Fe(H2O)]+, through Cu -O H -O -Fe -O -H O -Cu hydrogen bonds of coordinating H2O. In this complex, FeIII ions are in almost square-planar surroundings. The temperature dependences of the magnetic susceptibilities of the complex have been studied in the 4.2–300 K range, indicating the presence of an antiferromagnetic interactions between metal ions.  相似文献   

9.
Treatment of [Ph3P+-CH = CH-NHC6H3(2-OH)(4-NO2)]Cl- with ethanolic KOH leads to proton abstraction not from nitrogen, but from oxygen to give a betaine-type compound Ph3P+-CH = CHNHC6H3 · (2-O-)(4-NO2). Its structure was proved by means of X-ray diffraction. The C = C distance [1.341(3) Å] unambiguously points to a double bond. Single crystals of the betaine are monoclinic, space group P2(1)/c; unit cell parameters: a 9.028(4), b 14.066(6), and c 18.799(10) Å; 90, 76.23(4), and 90°. The unit cell contains two dimers bound by strong inter- and intermolecular hydrogen bonds. Previously published IR and 1H NMR data do not contradict the betaine structure of the compound obtained.  相似文献   

10.
Syntheses within the system CuO-SeO2-H2O revealed four copper(II)-oxo-selenites. The crystal structures of these compounds were determined by single crystal X-ray techniques. Chemical formulae, lattice parameters and space groups are: Cu2O(SeO3)-I [a=8.925 (1) Å, P213], Cu2O(SeO3)-II [a=6.987 (5) Å,b=5.953 (4) Å,c=8.429 (6) Å, =92.17 (3)°, P21/n], Cu4O(SeO3)3-I [a=15.990 (8) Å,b=13.518 (8) Å,c=17.745 (12) Å, =90.49 (5)°, P21/a], and Cu4O(SeO3)3-II [a=7.992 (6) Å,b=8.141 (6) Å,c=8.391 (6) Å, =77.34 (3)°, =65.56 (3)°, =81.36 (3)°, ].All the Cu atoms are-with one exception-[4], [4+1], and [4+2] coordinated by O atoms. The four nearest O atoms are more or less distorted square planar arranged. Within the CuO4 squares the Cu-O bond lengths are significantly shorter for the [4] coordinated O atoms as compared with those of the [4+1] and [4+2] coordinated Cu atoms. The exception in the coordination of the Cu atoms is the Cu(1) atom in Cu2O(SeO3)-I with the site symmetry 3, which is trigonal dipyramidal [5] coordinated. A common feature of these four crystal structures is, that O atoms outside the SeO3 groups are tetrahedrally coordinated by four Cu(II) atoms. The Se atoms are as usual [3] coordinated, building up SeO3 pyramids. In all these four compounds the copper-oxygen polyhedra are combined to a three-dimensional network.
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11.
The structure of bis(ethylenediamine)nickel(II)tetracyanopalladate(II), Ni(NH2CH2CH2NH2)2Pd(CN)4, has been determined from three-dimensional X-ray data, using Weissenberg photographs. The compound crystallizes with two molecules in the monoclinic space group P21/n with a=7.174(10), b=10.740(15), c=10.135(15) Å, =115.0(5)°. The measured and the calculated density is 1.83 g/cm3. Anisotropic refinement gave a finalR factor of 10.2%. The structure consists of infinite chains, -Pd-C-N-Ni-N-C-, parallel to thec-axis. Two trans-nitrogen atoms of the square Pd(CN) 4 2– are linked to Ni, leading thus to a polynuclear compound with an octahedral [NiN6] group in agreement with visible and infrared spectra. The trans-Ni(NH2CH2CH2NH2)2(NC)2-group has an asymmetric gauche ()-conformation. Average distances are: Pd-C: 1.96 Å, CN: 1.15 Å, Ni-N: 2.08 Å.
Zusammenfassung Die Struktur von Bis(äthylendiamin)nickel(II)-tetracyanopalladat(II), Ni(NH2CH2CH2NH2)2Pd(CN)4, wurde mit Hilfe von Weissenbergaufnahmen ermittelt. Die Substanz kristallisiert mit zwei Formeleinheiten in der monoklinen Raumgruppe P21/n mit den Zelldimensionen a=7,174(10), b=10,740(15), c=10,135(15) Å, =115,0(5)°. Die gemessene und die berechnete Dichte betragen beide 1,83 g/cm3. Die, Verfeinerung unter Berücksichtigung anisotroper Temperaturfaktoren führte zu einem. R-Wert von 10,2%. Unendlich lange-Pd-C-N-Ni-N-C-Ketten sind parallel derc-Achse angeordnet. In Übereinstimmung mit den Spektren im sichtbaren und infraroten Bereich handelt es sich um einen polynuklearen Komplex, indem die trans-Cyanidgruppen von Pd(CN) 4 2– als ambidente Liganden zu einer oktaedrischen [NiN6]-Koordinationseinheit führen. Die trans-Ni(NH2CH2CH2NH2)2(NC)2-Gruppe weist eine asymmetrische gauche ()- Konformation auf. Mittlere Atomabstände betragen: Pd-C=1,96 Å. CN=1,15 Å, Ni-N=2,08 Å.

Résumé La structure du tétracyanopalladate (II) de bis (éthylènediamine) nickel (II) a été déterminée à partir de données tri-dimensionnelles aux rayons X, avec des photographies de Weissenberg. Le composé cristallise avec deux molécules dans le groupe spatial monoclinique P21/n avec les param ètres a=7.174 (10), b=10.740 (15), c=10.135 (15) Å, =115.0 (5)°. La densité mesurée et calculée est 1,83 g/cm3. L'amélioration anisotrope donne un facteurR final de 10,2%. La structure se présente comme des chaînes infinies -Pd-C-N-Ni-N-C, parallèles à l'axec. Deux atomes d'azote trans du groupe carré Pd(CN) 4 2– sont liés à Ni, conduisant ainsi à un composé polycyclique avec un groupe [NiN6] octaédrique, ce qui est en accord avec le spectre visible et infra-rouge. Le groupe trans-Ni (NH2CH2CH2NH2)2(NC)2 a une conformation assymétrique gauche (). Les distances moyennes sont Pd-C: 1,96 Å, CN:1,15 Å, Ni-N: 2,08 Å.


Dedicated to the memory of Professor Hans-Ludwig Schläfer.  相似文献   

12.
Crystals of [Cu(o-Andp)(H2O)2] · 2H2O (where o-Andp2–is -anisidine-N,N-di-3-propionate) were synthesized and studied using X-ray diffraction analysis. The crystals are triclinic: a= 12.063(1) Å, b= 12.483(3) Å, c= 13.586(2) Å, = 91.29(1)°, = 111.67(1)°, = 104.00(1)°, V= 1830.5(5) Å3, space group P , Z= 2, and R= 0.0528 for 5965 reflections with I2(I). The two crystallographically independent complexes are isostructural. The tetragonal–bipyramidal coordination of copper(III) involves three O atoms, the N atom of the tetradentate ligand o-Andp2–, and two O atoms from water. The aminodipropionate group of the ligand (average Cu–O 1.939 Å and Cu–N 2.051 Å) and one of the coordinated water molecules (Cu–O(w) 1.991 Å) lie in the equatorial plane. The second water molecule (Cu–O(w) 2.32 Å) and the methoxy O atom of o-Andp2–(Cu–O 2.37 Å) are in the apical positions of the bipyramid.  相似文献   

13.
The three copper(II)-arsenates were synthesized under hydrothermal conditions; their crystal structures were determined by single-crystal X-ray diffraction methods:Cu3(AsO4)2-III:a=5.046(2) Å,b=5.417(2) Å,c=6.354(2) Å, =70.61(2)°, =86.52(2)°, =68.43(2)°,Z=1, space group ,R=0.035 for 1674 reflections with sin / 0.90 Å–1.Na4Cu(AsO4)2:a=4.882(2) Å,b=5.870(2) Å,c=6.958(3) Å, =98.51(2)°, =90.76(2)°, =105.97(2)°,Z=1, space group ,R=0.028 for 2157 reflections with sin / 0.90 Å–1.KCu4(AsO4)3:a=12.234(5) Å,b=12.438(5) Å,c=7.307(3) Å, =118.17(2)°,Z=4, space group C2/c,R=0.029 for 1896 reflections with sin / 0.80 Å–1.Within these three compounds the Cu atoms are square planar [4], tetragonal pyramidal [4+1], and tetragonal bipyramidal [4+2] coordinated by O atoms; an exception is the Cu(2)[4+1] atom in Cu3(AsO4)2-III: the coordination polyhedron is a representative for the transition from a tetragonal pyramid towards a trigonal bipyramid. In KCu4(AsO4)3 the Cu(1)[4]O4 square and the As(1)O4 tetrahedron share a common O—O edge of 2.428(5) Å, resulting in distortions of both the CuO4 square and the AsO4 tetrahedron. The two Na atoms in Na4Cu(AsO4)2 are [6] coordinated, the K atom in KCu4(AsO4)3 is [8] coordinated by O atoms.Die drei Kupfer(II)-Arsenate wurden unter Hydrothermalbedingungen gezüchtet und ihre Kristallstrukturen mittels Einkristall-Röntgenbeugungsmethoden ermittelt:Cu3(AsO4)2-III:a = 5.046(2) Å,b = 5.417(2) Å,c = 6.354(2) Å, = 70.61 (2)°, = 86.52(2)°, = 68.43(2)°,Z = 1, Raumgruppe ,R = 0.035 für 1674 Reflexe mit sin / 0.90 Å–1.Na4Cu(AsO4)2:a = 4.882(2) Å,b = 5.870(2) Å,c = 6.958(3) Å, = 98.51(2)°, = 90.76(2)°, = 105.97(2)°,Z = 1, Raumgruppe ,R = 0.028 für 2157 Reflexe mit sin / 0.90 Å–1.KCu4(AsO4)3:a = 12.234(5) Å,b = 12.438(5) Å,c = 7.307(3) Å, = 118.17(2)°,Z = 4, Raumgruppe C2/c,R = 0.029 für 1896 Reflexe mit sin / 0.80 Å–1.Die Cu-Atome in diesen drei Verbindungen sind durch O-Atome quadratisch planar [4], tetragonal pyramidal [4 + 1] und tetragonal dipyramidal [4 + 2]-koordiniert; eine Ausnahme ist das Cu(2)[4 + 1]-Atom in Cu3(AsO4)2-III: Das Koordinationspolyeder stellt einen Vertreter des Übergangs von einer tetragonalen Pyramide zu einer trigonalen Dipyramide dar. In KCu4(AsO4)3 haben das Cu(1)[4]O4-Quadrat und das As(1)O4-Tetraeder eine gemeinsame O—O-Kante von 2.428(5) Å, was eine Verzerrung der beiden Koordinationsfiguren CuO4-Quadrat und AsO4-Tetraeder bedingt. Die zwei Na-Atome in Na4Cu(AsO4)3 sind durch O-Atome [6]-koordiniert, das K-Atom in KCu4(AsO4)3 ist [8]-koordiniert.
Zur Kristallchemie dreier Kupfer (II)-Arsenate: Cu3(AsO4)2-III, Na4Cu(AsO4)2 und KCu4(AsO4)3
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14.
Complex of podand 1,2-bis(2-(o-hydroxyphenoxy)ethyloxy)ethane (L) with potassium thiocyanate, [K2(NCS)2L2] (I) was synthesized and studied using X-ray diffraction analysis: space group P , a = 7.771 Å, b = 11.711 Å, c = 11.965 Å, = 72.22°, = 79.21°, = 89.07°, Z = 1. Structure I was solved by direct method and anisotropically refined by the full-matrix least-squares method to R = 0.040 for all 4370 independent reflections (CAD4 autodiffractometer, MoK ). Structure I contains [K(NCS)L] monomers of the host–guest type united into centrosymmetrical [K2(NCS)2L2] dimers via two bridging OH groups (one group from two L podands). In the monomer, the L podand appears as though to envelope the octacoordinated K+ cation, whose the coordination polyhedron is a strongly distorted hexagonal bipyramid with all six oxygen atoms of the L podand in its base and the N atom of the SCN ligand and the O atom of one of OH group of the neighboring (in dimer) L podand at its axial vertices. Molecules of I in crystal are joined through the O–H···N hydrogen bonds to form broad infinite chains along the x-axis.  相似文献   

15.
Summary Reaction of MoOCl3 with Me3SiN3 m THF followed by addition of tertiary phosphine oxides, RPO3(R3=Ph3, Ph2Et, Ph2Me), gives [MoCl2(NH)O(OPR3)2]. The crystal and molecular structure of the compound has been determined by x-ray diffraction methods. The complex crystallises in the monoclinic space group P21 /a with four molecules in a unit cell having dimensions a=15.667(8) Å, b=20.135(9) Å, c=9.726(7) Å and =95.01(1) Å. A total of 3510 reflections were collected by counter techniques using MoK radiation. The structure was refined on 2597 reflections with I > 2.58 (I) by full matrix least squares, using anisotropic temperature factors for all nonhydrogen atoms, to give a final R factor of 0.082. The overall configuration of the distorted octahedral complex istrans-dichloro-cis-bis[ethyl(diphenyl)phosphineoxide]cis-(oxo) imido with the molybdenum formally in the oxidation state (VI). The imido hydrogen has been located, and the Mo-N-H system is nonlinear.  相似文献   

16.
The potential functions of internal rotation around the C -S bond in the C6H5S(O)CH3 and C6H5S(O)CF3 molecules were obtained by ab initio MP2(full)/6-31+G* calculations. The stationary points were identified by solving the vibrational problems. The structures in which the plane of the C -S-C bonds is approximately perpendicular to the benzene ring plane correspond to the energy minimum. The barriers to rotation around the C -S bond, corrected for the zero-point vibration energy, are 21.29 [C6H5S(O)CH3] and 28.98 [C6H5S(O)CF3] kJ mol−1. The bond angles (deg) are as follows: 95.7 (CSC), 107.1 (C SO), 106.3 (C SO) in C6H5S(O)CH3; 93.5 (CSC), 108.2 (C SO), 105.2 (C SO) in C6H5S(O)CF3. The bond lengths are as follows (Å): 1.520 (S=O), 1.804 (C -S), 1.810 (C -S) in C6H5S(O)CH3; 1.507 (S=O), 1.799 (C -S), 1.870 (C -S) in C6H5S(O)CF3. According to the results of NBO calculations, the formally double S=O bond consists of a strongly polarized covalent σ bond (S→O) and an almost ionic bond. An increase in the S=O bond multiplicity relative to a single bond is mainly due to hyperconjugation by the mechanism n(O)→σ*(C -S) and n(O)→σ*(C -S) and, to a lesser extent, by interaction of the oxygen lone electron pairs with the Rydberg orbitals of the S atoms, characterized by a large contribution of the d component.__________Translated from Zhurnal Obshchei Khimii, Vol. 75, No. 1, 2005, pp. 96–104.Original Russian Text Copyright © 2005 by Bzhezovskii, Il’chenko, Chura, Gorb, Yagupol’skii.  相似文献   

17.
The structure of 1-(3,5-dimethyl-2-furyl)-3-(p-tolyl)-prop-2-en-1-one, C16H16O2 is determined by single-crystal x-ray diffractometry. Crystals are triclinic, , a=7.381(7), b=8.871(5), c=10.745(13) Å, =93.53(7), =102.25(8),=95.43(7)°, V=682(1) Å3, Z=2, dcalc=1.170 g cm–3, (Cu K)=1.54178 Å,=5.697 cm–1, M=270.30, F(000)=256, R=0.077 for 1601 unique observed reflections. The trans-geometry of the C=C double bond, thes-cis-geometry of the C=C-C=O moiety, and thes-trans arrangement of the carbonyl and furane oxygen atoms are proved.  相似文献   

18.
The crystal structure of an unusual dimeric Ni(II) complex with 3-imidazoline nitroxide LH=C9H14N2O2 of the formula Ni2(LH)4 has been determined. The structure is molecular, space group P21/c, with a=12.150(3) Å, b=11.229(3) Å, c=15.780(4) Å, =101.59(3)o, and d calc =1.54 g/cm3, for Z=2; V=2109(1) Å3, R=0.059. In the centrosymmetric dimer, the Ni...Ni distance is 3.254(2) Å; the coordination polyhedron of Ni is a square pyramid (the coordination number is 5) formed by the donor O and N atoms of LH ligands acting as the bidentate-cyclic and bidentate bridged-cyclic structures. The Ni–O and Ni–N distances are 1.989(7) and 2.032(8) Å, respectively (for the atoms forming the pyramid base), and 2.000(8) Å to the apical N atom. The Ni atom is displaced from the base to the apex of the pyramid by 0.35 Å. The interatomic distances and the bond angles in the ligands agree with those for the previously studied M(LR)2 complexes. The distances between the Ni(II) ions and the O O atoms inside the Ni(LH)2 fragments are 5.39(1) and 5.45(1) Å, the intermolecular Ni...O distances exceed 6 Å, and the O...O distances are as long as 4.73(1) Å.Institute of Inorgamic Chemistry, Siberian Branch, Russian Academy of Sciences. Translated fromZhurnal Stukturnoi Khimii, Vol. 34, No. 3, pp. 80–85, May–June 1993.Translated by T. Yudanova  相似文献   

19.
Summary The crystal structure of the dinuclear complex [Cu2(C26H30-N4O2)(H2O)2](BF4)2 was determined by x-ray crystallography. The crystals are triclinic, P¯1, witha = 10.945(5),b = 8.703(5),c = 8.495(5) Å, = 103.86(3)°, = 105.73(3)°, = 85.77(3)°, V = 756 Å3 Dc = 1.65 g cm–3 for Z = 1. The copper(II) atoms are 5-coordinate and square-pyramidal. Selected bond distances are: Cu-N, 1.91 Å (mean); Cu-O(base) = 1.90(1) and 1.91(1) Å; Cu-O(apical) = 2.47(1) Å; There are O(water)-H ... F interionic hydrogen bonds in the structure. The Cu .. Cu distance is 2.847 Å.  相似文献   

20.
Investigations in the system Sb-Se-NaOH-H2O, hydrothermal conditions, yielded crystals of the compound Na3SbSe3·3Sb2O3·0,5Sb(OH)3. The structure of this compound (a=14.40 Å,c=5.568 Å; space group P 63-C 6 6 ;Z=2) was determined from 985 independent X-ray intensities — collected on an automaticWeissenberg type diffractometer — by thePatterson method and refined by the least squares method toR=8.3% (with -weighting 5.9%). The structure consists of SbO3 pyramids which are connected via common oxygen corners to tubes parallel [001]. These tubes and SbSe3 pyramids are combined by Na atoms to a framework. The Sb(OH)3 groups are statistically located within the channels of the tubes.
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