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1.
Crystal Structures of the Fluorochloroplatinates(IV) cis-[(C5H5N)2CH2][PtF4Cl2], trans-[(C5H5N)2CH2][PtF4Cl2] · H2O, and [(C5H5N)2CH2][PtF5Cl] The complex ions cis-[PtF4Cl2]2?, trans-[PtF4Cl2]2? and [PtF5Cl]2? have been synthesized by stereoselective ligand exchange reactions utilizing the trans effect and are separated by ion exchange chromatography on diethylaminoethyl cellulose. These anions form stable AB-type salts with the doubly charged cation dipyridiniomethane, [(C5H5N)2CH2]2+. X-ray structure determinations on single crystals of cis-[(C5H5N)2CH2][PtF4Cl2] ( 1 ) (monoclinic, space group P21/n with a = 10.379(10), b = 9.635(2), c = 13.738(2) Å, β = 99.142(10)°, Z = 4), trans-[(C5H5N)2CH2][PtF4Cl2] · H2O ( 2 ) (triclinic, space group P1 with a = 7.757(4), b = 10.059(7), c = 10.408(6) Å, α = 82.49(5), β = 68.92(4), γ = 75.46(4)°, Z = 2) and [(C5H5N)2CH2][PtF5Cl] ( 3 ) (orthorhombic, space group Pnma with a = 10.394(3), b = 13.320(2), c = 9.2694(10) Å, Z = 4), reveal the perfect ordering of the anion sublattice. The stronger trans influence of Cl compared with F is observed in asymmetric axes $ {\rm F}^ \bullet $? Pt? Cl′. The bond lengths Pt? $ {\rm F}^ \bullet $ are 0.026 Å (1.4%) longer and the Pt? Cl′ distances are 0.078 Å (3,3%) shorter in comparison with those of symmetrically coordinated axes. The weakening of the Pt? $ {\rm F}^ \bullet $ bond and the strengthening of the Pt? Cl′ bond is better recognizable from shifts of the stretching vibrations by 8% to lower and by 13% to higher frequencies, respectively. Correspondingly, the valence force constants are found to be 15% lower and 22% higher. The trans influence is observed most distinctly in the 19F-nmr spectra exhibiting the coupling constant 1J($ {\rm F}^ \bullet $Pt) to be 29% smaller than 1J(FPt).  相似文献   

2.
Synthesis, Crystal Structures, and Vibrational Spectra of [(Ph3P)2N]2[(W6Cl )I ] · 2 Et2O · 2 CH2Cl2 and [(Ph3P)2N]2[(W6Cl )(NCS) ] · 2 CH2Cl2 By treatment of [(W6Cl)I]2– with (SCN)2 in dichloromethane at –20 °C the hexaisothiocyanato cluster anion [(W6Cl)(NCS)]2– is formed. X‐ray structure determinations have been performed on single crystals of [(Ph3P)2N]2[(W6Cl)I] · 2 CH2Cl2 · 2 Et2O ( 1 ) (triclinic, space group P1, a = 10.324(5), b = 14.908(3), c = 17.734(8) Å, α = 112.78(2)°, β = 99.13(3)°, γ = 92.02(3)°, Z = 1) and [(Ph3P)2N]2[(W6Cl)(NCS)] · 2 CH2Cl2 ( 2 ) (triclinic, space group P1, a = 11.115(2), b = 14.839(2), c = 17.036(3) Å, α = 104.46(1)°, β = 105.75(2)°, γ = 110.59(1)°, Z = 1). The thiocyanate ligands of 2 are bound exclusively via N atoms with W–N bond lengths of 2.091–2.107 Å, W–N–C angles of 173.1–176.9° and N–C–S angles of 178.1–179.3°. The vibrational spectra exhibit characteristic innerligand vibrations at 2067–2045 (νCN), 879–867 (νCS) and 490–482 (δNCS). Based on the molekular parameters of the X‐ray determination of 1 the vibrational spectra of the corresponding (n‐Bu4N) salt of 1 are assigned by normal coordinate analysis. The valence force constants are fd(WW) = 1.61, fd(WI) = 1.23 and fd(WCl) = 1.10 mdyn/Å.  相似文献   

3.
Preparation, Spectroscopic Characterization, and Crystal Structures of [(C5H5N)2CH2][PtCl5(SCN)] and cis -[(C5H5N)2CH2][PtCl4(SCN)2] By treatment of [PtCl6]2– with SCN in aqueous solution a mixture of chlorothiocyanatoplatinates(IV) is formed, from which [PtCl5(SCN)]2– and cis-[PtCl4(SCN)2]2– have been separated by ion exchange chromatography on diethylaminoethyl cellulose. X-Ray structure determinations on single crystals of [(C5H5N)2CH2][PtCl5(SCN)] ( 1 ) (tetragonal, space group P 43, a = 7.687(1), c = 29.698(4), Z = 4) and cis-[(C5H5N)2CH2][PtCl4(SCN)2] ( 2 ) (monoclinic, space group P 21/n, a = 11.2467(9), b = 15.0445(10), c = 11.3179(13), β = 92.840(9)°, Z = 4) show, that the thiocyanate groups are coordinated via S atoms with average Pt–S distances of 2.339 Å and Pt–S–C angles of 104.7° up to 107.1°. Using the molecular parameters of the X-ray determinations the low temperature (10 K) IR and Raman spectra have been assigned by normal coordinate analyses. The valence force constants of the S–Pt–Cl˙ axes are fd(PtS) = 1.81 ( 1 ) and 1.87 ( 2 ), fd(PtCl × ) = 1.77 ( 1 ) and 1.81 ( 2 ), of the Cl–Pt–Cl axes are fd(PtCl) = 1.93 ( 1 ) and 1.90 mdyn/Å ( 2 ). The 195Pt NMR spectra from dichlormethane solutions exhibit each one sharp signal at 3975.6 ( 1 ) and 3231.6 ppm ( 2 ), respectively.  相似文献   

4.
Synthesis, Vibrational Spectra, and Crystal Structure of ( n ‐Bu4N)2[(W6Cl )F ] · 2 CH2Cl2 and 19F NMR Spectroscopic Evidence of the Mixed Cluster Anions [(W6Cl )F Cl ]2–, n = 1–6 The reaction of (n‐Bu4N)2[(W6Cl)Cl] with CF3COOH in dichloromethane gives intermediately a mixture of the cluster anions [(W6Cl)(CF3COO)Cl]2–, n = 1–6. By treatment with NH4F the outer sphere coordinated trifluoracetato ligands are easily substituted and the components of the series [(W6Cl)FCl], n = 1–6 are formed and characterized by their distinct 19F NMR chemical shifts. An X‐ray structure determination has been performed on a single crystal of (n‐Bu4N)2[(W6Cl)F] · 2 CH2Cl2 (orthorhombic, space group Pbca, a = 15.628(4), b = 17.656(3), c = 20.687(4) Å, Z = 4). The low temperatur IR (60 K) and Raman (20 K) spectra are assigned by normal coordinate analysis based on the molecular parameters of the X‐ray determination. The valence force constants are fd(WW) = 1.89, fd(WF) = 2.43 and fd(WCl) = 0.93 mdyn/Å.  相似文献   

5.
Heavy Metal π-Complexes. IX. The Chain Polymers [(1,2- (CH3)2C6H4BiCl3)2], [(1,3- (CH3)2C6H4BiCl3)2] and [(1,4- (CH3)2C6H4BiCl3)2] In the crystal structures of the three solid state complexes (C6H4(CH3)2BiCl3 (C6H4(CH3)2 = o-xylene: 1 , m-xylene: 2 , p-xylene: 3 ) quasi-dimeric units of almost undistorted, arene coordinated BiCl3 fragments can be found that are further associated via additional Bi? Cl contacts to form one-dimensional polymeric chains. Whereas the chains of 2 and 3 are constituted by Bi2Cl2 four-membered rings only, further Cl-bridging in 1 leads to additional trigonal-bipyramidal arrangements with Bi atoms exhibiting coordination numbers of 3 + 3 + 1 and 3 + 2 + 1, respectively (prim. + sec. Cl contacts + arene). The arene-metal bonding is characterized by Bi-arene distances in the range from 297 – 306 pm, including ring slippages of 24 –41 pm and 73 pm with the Bi atoms being six and seven coordinated, respectively. The direction of this slipping with respect to the arene's methylation sites cannot be understood in terms of electronic influences but is shown to be caused by steric demands. The values IP1 of the arenes prove to determine the colours of the complexes.  相似文献   

6.
Iodostannates with Polymeric Anions: (Me3PhN)4 [Sn3I10], [Me2HN–(CH2)2–NMe2H]2 [Sn3I10], and [Me2HN–(CH2)2–NMe2H] [Sn3I8] The polymeric iodostannate anions in (Me3PhN)4 [Sn3I10] ( 1 ) and [Me2HN–(CH2)2–NMe2H]2 [Sn3I10] ( 2 ) consist of Sn3I12‐trioctahedra, which share four common iodine atoms with adjacent units to form infinite layers in 1 and polymeric chains in 2 . In the anion of [Me2HN–(CH2)2–NMe2H] [Sn3I8] ( 3 ) distorted SnI6 octahedra sharing common edges and vertices form a two‐dimensional network. (Me3PhN)4 [Sn3I10] ( 1 ): Space group C2/c (No. 15), a = 2406.9(2), b = 968.26(7), c = 2651.7(2) pm, β = 111.775(9), V = 5738.9(8) · 106 pm3; [Me2HN–(CH2)2–NMe2H]2 [Sn3I10] ( 2 ): Space group P21/n (No. 14), a = 1187.2(1), b = 1554.4(1), c = 1188.9(1) pm, β = 116.620(8), V = 1961.4(3) · 106 pm3; [Me2HN–(CH2)2–NMe2H] [Sn3I8] ( 3 ): Space group P21/c (No. 14), a = 1098.9(2), b = 803.93(7), c = 1571.5(2) pm, β = 102.96(1), V = 1352.9(2) · 106 pm3.  相似文献   

7.
Synthesis and Structure Investigations of Iodocuprates(I). XV Iodocuprate(I) with Solvated Cations: [Li(CH3CN)4] [Cu2I3] and [Mg{(CH3)2CO}6][Cu2I4] [Li(CH3CN)4][Cu2I3] 1 and [Mg((CH3)2CO)6][Cu2I4] 2 were prepared by reactions of CuI with LiI in acetonitrile and of CuI with MgI2 in acetone. 1 crystallizes orthorhombic, Pnma, a = 552.7(2), b = 1258.8(8), c = 2516(1) pm, z = 4. [Li(CH3CN)4]+ cations are located between rod packings of CuI4 tetrahedra double chains [(CuI2/2I2/4)2]? parallel to the axis. Short intermolecular anion/cation contacts were observed. The crystal structure of 2 (monoclinic, P21/n, a = 1840(2), b = 1059.2(2), c = 1879(2)pm, β = 112.94(4)°, z = 4) is built up by [Mg((CH3)2CO)6]2+ cations forming a simple hexagonal sphere packing. The binuclear anions [Cu2I4]2? occupy holes in the trigonal prismatic channels formed by the cations.  相似文献   

8.
Transition Metal‐substituted Phosphaalkenes. 42 Reactivity of the Ferriophosphaalkenes [(η5‐C5Me5)(CO)2FeP=C(NR )R2] (NR = NMe2, NC5H10, R2 = Ph, t Bu) towards Protic Acids, Alkylation Reagents, and [{( Z )‐Cyclooctene}Cr(CO)5] The reaction of equimolar amounts of [(η5‐C5Me5)(CO)2FeP=C(NR )R2] ( 2 a : NR = NMe2, R2 = Ph; 2 b : NMe2. tBu; 2 c : NC5H10, Ph) and etherial HBF4 gave rise to the formation of [(η5‐C5Me5)(CO)2FeP(H)C(NR )R2] (BF4) ( 3 a – c ) which were isolated as light red powders. Compounds 2 a – c were converted into [(η5‐C5Me5)(CO)2FeP(Me)C(NR )R2] (SO3CF3) ( 4 a – c ) by treatment with methyl trifluoromethane sulfonate. In addition 2 a and Me3SiCH2OSO2CF3 afforded light red [(η5‐C5Me5)(CO)2FeP(CH2SiMe3)C(NMe2)Ph](SO3CF3) ( 5 ). The black complex [(η5‐C5Me5)(CO)2FeP{Cr(CO)5}C(NMe2)Ph] ( 6 ) resulted from the combination of 2 a with [{(Z)‐cyclooctene}Cr(CO)5]. The novel products were characterized by elemental analyses and spectra (IR, 1H‐, 13C‐ und 31P‐NMR).  相似文献   

9.
LuF[SeO3] and LuCl[SeO3]: Two Non‐Isotypic Halide Oxoselenates(IV) of Lutetium Despite the formal similarity of LuF[SeO3] and LuCl[SeO3] both compounds show significant structural differences due to the different positions of the halide anions (X) within the pentagonal bipyramids [LuO5X2]9−. However, both oxoselenates(IV) have these pentagonal bipyramids as basic modules in common that are connected via O2− edges to chains. LuCl[SeO3] crystallizes orthorhombically in space group Pnma (no. 62; a = 714.63(7), b = 681.76(7) and c = 864.05(9) pm; Z = 4). The structure is isotypic to that one recently presented for ErCl[SeO3]. With a single Cl anion in each an apical and an equatorial position, the chains have to be inclined with an angle of about 54° relative to each other to get connected alternately by common Cl corners and bridging [SeO3]2− pyramids. In contrast to that, LuF[SeO3] which crystallizes triclinically in space group (no. 2; a = 644.85(6), b = 684.41(7), c = 427.98(4) pm, α = 94.063(5), β = 96.484(5) and γ = 91.895(5)°; Z = 2) takes a structural motif already known from CsTmCl2[SeO3]. Owing to the apical position of both halide anions it is now possible to connect the chains directly via discrete Ψ1‐tetrahedral [SeO3]2− groups to layers. The same layers are present in LuF[SeO3] and without the formal alkali‐metal halide unit (CsCl) of the CsTmCl2[SeO3]‐type compounds, the layers can also be connected directly by common F corners to a three‐dimensional array. Torch‐sealed evacuated silica ampoules were used for the synthesis of both lutetium(III) halide oxoselenates(IV). For LuF[SeO3] these vessels have been graphitized before to prevent them from oxosilicate‐producing side‐reactions with the applied fluoride. The synthesis of LuCl[SeO3] required Lu2O3 and SeO2 in a molar ratio of 1 : 6 with a surplus of an eutectic RbCl/LiCl mixture as fluxing agent and an annealing period of five weeks at a temperature of 500 °C, whereas Lu2O3, LuF3 and SeO2 (in a molar ratio of 1 : 1 : 3) with CsBr as flux were converted to LuF[SeO3] at 750 °C within six days.  相似文献   

10.
The title compounds 3‐5 are accessible by treatment of P(C6H4CH2NMe2)3( 1 ) with CuX ( 2a : X = Cl, 2b : X = Br, 2c : X = I) in the ratio of 1:1 or 1:2 in very good yields. Reaction of 1 with equimolar amounts of 2a affords the copper(I) chloride [P(C6H4CH2NMe2)3]CuCl ( 3 ). With a further equivalent of 2a homobimetallic [P(C6H4CH2NMe2)3]Cu2Cl2 ( 4 ) is formed, which also can be synthesized by the reaction of 1 with two equivalents of 2a. Complex 3 reacts with CuX (X = Br, I)to afford [P(C6H4CH2NMe2)3]Cu2ClX ( 5a : X = Br; 5b : X = I) in which mixed halides are present. The newly synthesized complexes 3‐5 were characterized by elemental analyses, by their IR‐, 1H‐, 13C{1H}‐ and 31P{1H}‐NMR spectra as well as by mass spectrometrical studies. The solid‐state structures of complexes 3 and 4 are reported. Mononuclear 3 crystallizes in the monoclinic space group P21/c with the cell parameters a = 14.285(2), b = 10.853(2), c = 17.425(2) Å , β = 103.310(10)?, V = 2628.9(7) Å 3 and Z = 4 with 4053 observed unique reflections; R1 = 0.0314. The crystal structure of 3 consists of monomeric molecules with planar coordinated copper(I) centres (CuClNP). Homobimetallic 4 crystallizes in the monoclinic space group P21/n with a = 23.905(4), b = 10.874(3), c = 25.314(5), β = 99.130(10)?, V = 6497(2) /Aring; 3 and Z = 4 with 9021 observed unique reflections; R1 = 0.0480. In 4 one of two copper(I) centres possesses a distorted trigonal‐pyramidal environment, while the other one is almost square‐pyramidal coordinated. The Cu2Cl2 segment resembles to a building block which is set up by a contact ion pair consisting of Cu+ and [CuCl2] , respectively.  相似文献   

11.
Crystal Structures of [Ph3PMe]Cl·CH2Cl2, [Ph4P]NO3·CH2Cl2, and [Ph4P]2[SiF6]·CH2Cl2 The crystal structures of the title compounds are determined by X‐ray diffraction. In all cases, the included dichloromethane molecules as well as the phosphonium cations are involved to form hydrogen bridges with the anions. [Ph3PMe]Cl·CH2Cl2 ( 1 ): Space group , Z = 2, lattice dimensions at 100 K: a = 890.3(1), b = 988.0(1), c = 1162.5(1) pm, α = 106.57(1)°, β = 91.79(1)°, γ = 92.60(1)°, R1 = 0.0253. [Ph4P]NO3·CH2Cl2 ( 2 ): Space group P21/n, Z = 4, lattice dimensions at 193 K: a = 1057.0(1), b = 1666.0(1), c = 1358.9(1) pm, β = 100.10(1)°, R1 = 0.0359. [Ph4P]2[SiF6]·CH2Cl2 ( 3 ): Space group , Z = 2, lattice dimensions at 193 K: a = 1063.9(1), b = 1233.1(1), c = 1782.5(2) pm, α = 76.88(1)°, β = 83.46(1)°, γ = 72.29(1)°, R1 = 0.0332.  相似文献   

12.
During attempts to synthesize lanthanoid(III) fluoride oxoselenates(IV) with the simple composition MF[SeO3], not only Pr3F[SeO3]4, but also Pr5F[SiO4]2[SeO3]3 appeared as pale green crystalline by‐products in the case of praseodymium. Pr5F[SiO4]2[SeO3]3 crystallizes triclinically in space group P$\bar{1}$ (no. 2) with a = 701.14(5), b = 982.68(7), c = 1286.79(9) pm, α = 70.552(3), β = 76.904(3), γ = 69.417(3)° and Z = 2. The five crystallographically different Pr3+ cations on the general positions 2i show coordination numbers of eight and nine. [(Pr1)O8]13– and [(Pr2)O8]13– polyhedra are connected to$\bar{1}$ {[(Pr1, 2)2O12]18–} chains along the [100] direction. [(Pr3)O7F]12–, [(Pr4)O8F]14– and [(Pr4)O8F]14– polyhedra generate [F(Pr3, 4, 5)3O19]30– units about their central F anion in triangular Pr3+ coordination. These units form $\bar{1}$ {[F(Pr3, 4, 5)3O16]24–} strands, again running parallel to [100]. Their alternating connection with the $\bar{1}$ {[(Pr1, 2)2O12]18–} chains results in $\bar{1}$ {[Pr5O20F]26–} sheets parallel to the (001) plane. Like in the already known related compound Er3F[SiO4][SeO3]2, a three‐dimensional network $\bar{1}$ {[Pr5O17F]20–} is achieved without the contribution of both the tetravalent silicon and selenium components. However, two Si4+ and three Se4+ cations forming tetrahedral [SiO4]4– and ψ1‐tetrahedral [SeO3]2– units with all O2– anions guarantee the charge balance. The formation of Pr5F[SiO4]2[SeO3]3 was observed when praseodymium sesquioxide (Pr2O3: in‐situ produced from Pr and Pr6O11 in a molar ratio of 3/11:4/11),praseodymium trifluoride (PrF3) and selenium dioxide (SeO2) in 1:1:3 molar ratios were reacted with CsBr as fluxing agent for five days at 750 °C in evacuated fused silica (SiO2) ampoules.  相似文献   

13.
Synthesis, Crystal Structure, and Vibrational Spectra of (n-Bu4N)2[(Mo6I)(NCS)] By treatment of [(Mo6I)I]2– with (SCN)2 in dichloromethane at –20 °C the hexaisothiocyanato cluster anion [(Mo6I)(NCS)]2– is formed. The X-ray structure determination of (n-Bu4N)2[(Mo6I)(NCS)] · 2 Me2CO (monoclinic, space group P21/c, a = 13.168(5), b = 11.964(5), c = 24.636(5) Å, β = 104.960(5)°, Z = 2) shows, that the thiocyanate groups are coordinated exclusively via N atoms with Mo–N bond lengths of 2.141–2.150 Å, Mo–N–C angles of 166–178° and N–C–S-angles of 174–180°. The vibrational spectra exhibit characteristic innerligand vibrations at 2073–2054 (νCN), 846–844 (νCS) and 480–462 cm–1NCS).  相似文献   

14.
19F NMR Spectroscopic Evidence and Calculation of the Statistical Formation of Mixed Cluster Anions [(Mo6I Cl )F ]2?, n = 0–7, and Preparation of (TBA)2[(Mo6I )F ] The octa-μ3-iodo-hexafluoro-hexamolybdate(2?)ion [(Mo6I)F]2? is prepared for the first time. The system of the 21 innersphere mixed clusters (Mo6ICl)4+, n = 0–7 is formed by exchange of innersphere bound Cli against outersphere bound Ia on tempering solid [(Mo6Cl)I] at 400°C. Prolonged tempering leads to increasing average n values of the mixture, which is converted into the tetrabutylammonium salt (TBA)2[(Mo6ICl)F]. Using increments of chemical shifts and integral peak intensities the 54 19F-nmr signals of the 21 species (compound n = 8 is absent) are assigned and confirmed by the 2 D-19F/19F-COSY spectrum. From the measured intensities the distribution of the different compounds is determined and proves significant deviation from statistical occupation, revealing the preference of isomers with iodine atoms occupying edges of the innersphere cube and discrimination of those sharing diagonals of the faces. Moreover all compounds with n = 3 and 4 are present overaverage in comparison to the others.  相似文献   

15.
Azido Complexes of Vanadium(IV) and Vanadium(V): (Ph4P)2[VOCl2(μ‐N3)]2 and (Ph4P)2[VOCl(μ‐N3)(N3)2]2 (Ph4P)2[VOCl2(μ‐N3)]2 ( 1 ) was prepared by reaction of (Ph4P)[VO2Cl2] with trimethylsilylazide in the molar ratio 1:2 in dichloromethane solution to give dark green, moisture sensitive, non‐explosive single crystals. The reaction is accompanied by the formation of the dark blue side‐product (Ph4P)2[VOCl(μ‐N3)(N3)2]2 ( 2a ), which can be obtained as the main product by application of a large excess of Me3SiN3. Dark blue needles of 2a crystallize spontaneously from the CH2Cl2 solution within one hour at 4 °C. After standing at 4 °C under its mother liquid within 24 hours a first‐order phase transition of 2a occurs forming dark blue prismatic single crystals of 2b . According to single crystal X‐ray structure determinations, 2a and 2b crystallize in the same type of space group , however, with different lattice dimensions. The vanadium(IV) complex 1 is characterized by X‐ray structure determination and by vibrational spectroscopy (IR, Raman) as well as by EPR spectroscopy, whereas 2b is characterized by IR spectroscopy. 1 : Space group P21/n, Z = 2, a = 1009.5(1), b = 1226.6(2), c = 1943.0(2) pm, β = 98.42(1)°, R1 = 0.0672. The complex anion forms centrosymmetric units with V2N2‐four‐membered rings with a V···V distance of 335.6(1) pm and coordination number five on the vanadium(IV) atoms. 2a : Space group , Z = 1, a = 1089.0(2), b = 1097.1(2), c = 1310.1(2) pm, α = 92.99(1)°, β = 106.12(2)°, γ = 117.05(2)°, V = 1309.8(4) Å3, dcalc. = 1.440 g·cm?3, R1 = 0.0384. The complex anion forms centrosymmetric units of symmetry Ci with V2N2 four‐membered rings and VN bond lengths of 200.4(3) and 234.4(2) pm, respectively. The non‐bonding V···V distance amounts to 356.2(1) pm. 2b : Space group , Z = 1, a = 1037.3(2), b = 1157.6(2), c = 1177.2(2) pm, α = 98.48(2)°, ° = 103.82(2)°, γ = 106.33(2)°, V = 1281.8(4) Å3, dcalc. = 1.471 g·cm?3, R1 = 0.0724. The structure of the complex anion is similar to the anion of 2a with VN bond lengths of the four‐membered V2N2 ring of 203.3(4) and 235.2(4) pm, respectively, and a non‐bonding V···V distance of 357.5(1) pm.  相似文献   

16.
A Chloroacid of Trivalent Rhenium: Hydroxonium Decachloro Diaqua Trirhenate(III) Pentahydrate, H3O[Re3Cl10(H2O)2] · 5H2O . A chloroacid of rhenium(III), H3O[Re3Cl10(H2O)2] · 5H2O, was obtained at room temperature from a saturated solution of “ReCl3 · 2H2O” with an excess of NaCl in concentrated hydrochloric acid. The crystal structure (tetragonal, P41212 (Nr. 92); a = 1 150.9(2) pm; c = 1 592.2(6) pm; Z = 4; R = 0.086; Rw = 0.066) has been determined from four-circle diffractometer data. The structure contains isolated cluster anions, [Re3ClClCli,t (H2O)]?, which are enclosed by a cage of water molecules. These building units are connected with each other through a “strong” hydrogen-bonding system.  相似文献   

17.
Nitride Sulfide Chlorides of the Lanthanides. III. Synthesis and Crystal Structure of Pr5N3S2Cl2 By reacting praseodymium with sulfur, sodium azide and praseodymium trichloride in sealed, evacuated silica tubes (850°C, 7 d), the nitride sulfide chloride Pr5N3S2Cl2 is obtained in case of a 4:2:1:1 molar ratio of the reactants (Pr:S:NaN3:PrCl3). A slight excess of trichloride or the addition of NaCl as a flux supports the yield of brownish red, rod-shaped transparent crystals which prove to be stable against hydrolysis. The crystal structure (monoclinic, C2/m (no. 12), a = 1540.2(1), b = 400.92(3), c = 1656.3(1) pm, β = 101.24(1)°, Z = 4, R = 0.039, Rw = 0.028) was determined by means of X-ray single crystal data. Thus five crystallographically different cations (Pr3+) are present which with three distinct kinds of nitride anions (N3?) build up two types of translationally commensurate chains from interconnected [NPr4] tetrahedra. With an additional edge per “chain-link” in chain I, two single chains [NPr3/3ePr1/1t]3+ (?[NPr2]3+) of cis-edge connected [NPr4] tetrahedra (known from the Sm4N2S3-type structure) are condensed into the double chain [(N1){(Pr1)(2+2)/(2+2)e,e(Pr2)(2+1)/(2+1)e,v}(N2)(Pr3)1/1t]3+ (?[N2Pr3]3+). Chain II consists of two single chains [NPr2/2vPr2/1t] 6+ (?[NPr3]6+) of vertex-connected [NPr4] tetrahedra (known from the Sm3NS3-type structure), which are condensed to the double chain [(N3)(Pr4)2/2e(Pr5)2/2v]3+ (?[NPr2]3+) via an additional edge per “chain-link” too. Both types of chains are bundled along [010] like a closest packing of rods. Four crystallographically different but by X-ray diffraction indistinguishable anions S2? and Cl? hold both cationic double chains together and also adjust the charge balance in a molar ratio of 1 : 1.  相似文献   

18.
The purpose of this study was to calculate the structures and energetics of CH3OH$_{2}^{+}$(H2O)n and CH3SH$_{2}^{+}$(H2O)n in the gas phase: we asked how the CH3OH$_{2}^{+}$ and CH3SH$_{2}^{+}$ moieties of CH3OH$_{2}^{+}$(H2O)n and CH3SH$_{2}^{+}$(H2O)n change with an increase in n and how can we reproduce the experimental values ΔH°n−1,n. For this purpose, we carried out full geometry optimizations with MP2/6‐31+G(d,p) for CH3OH$_{2}^{+}$(H2O)n (n=0,1,2,3,4,5) and CH3SH$_{2}^{+}$(H2O)n (n=0,1,2,3,4). We also performed a vibrational analysis for all clusters in the optimized structures to confirm that all vibrational frequencies are real. All of the vibrational frequencies of these clusters are real, and they correspond to equilibrium structures. For CH3OH$_{2}^{+}$(H2O)n, when n increases, (1) the C O bond length decreases, (2) the C H bond lengths do not change, (3) the O H bond lengths increase, (4) the OCH bond angles increase, (5) the COH bond angles decrease, (6) the charge on CH3 becomes less positive, and (7) these predicted values, except for the O H bond lengths of CH3OH$_{2}^{+}$(H2O)n, approach the corresponding values in CH3OH. The C O bond length in CH3OH$_{2}^{+}$(H2O)5 is shorter than that in CH3OH$_{2}^{+}$ in the gas phase by 0.061 Å at the MP2/6‐31+G(d,p) level. Except for the S H bond lengths in CH3SH$_{2}^{+}$(H2O)n, however, the structure of the CH3SH$_{2}^{+}$ moiety does not change with an increase in n. © 2000 John Wiley & Sons, Inc. J Comput Chem 22: 125–131, 2001  相似文献   

19.
Preparation and Crystal Structure of trans-(Ph4As)2[OsCl2(NCS) (SCN) ], Vibrational Spectra and Normal Coordinate Analysis By treatment of trans-[OsCl2I4]2? with (SCN)2 in dichloromethane a mixture of different linkage isomers is formed, from which trans-[OsCl2(NCS)(SCN)]2? has been isolated by ion exchange chromatography on diethylaminoethyl cellulose. The X-Ray structure determination on a single crystal of trans-(Ph4As)2[OsCl2(NCS)(SCN)] (triclinic, space group P 1 , a = 12.505(5), b = 12.056(5), c = 19.833(5) Å, α = 108.047(5)°, β = 91.964(5)°, γ = 117.048(5)°, Z = 2) reveals that two cis-positioned Thiocyanate(N) groups are coordinated with Os? N? C angles of 172.1° and 173.0° and two cis-positioned Thiocyanate(S) groups are coordinated with Os? S? C angles of 106.9° and 108.7°. Using the molecular parameters of the X-Ray determination the low temperature (10 K) IR and Raman spectra of the (n-Bu4N) salt of the linkage isomer are assigned by a normal coordinate analysis based on a modified valence force field. The valence force constants are fd(OsN) = 1.63 and fd(OsS) = 1.30 mdyn/Å. Taking into account the trans influence a good agreement between observed and calculated frequencies is achieved.  相似文献   

20.
The crystal structure of Pt6Cl12 (β‐PtCl2) was redetermined ( ah = 13.126Å, ch = 8.666Å, Z = 3; arh = 8.110Å, α = 108.04°; 367 hkl, R = 0.032). As has been shown earlier, the structure is in principle a hierarchical variant of the cubic structure type of tungsten (bcc), which atoms are replaced by the hexameric Pt6Cl12 molecules. Due to the 60° rotation of the cuboctahedral clusters about one of the trigonal axes, the symmetry is reduced from to ( ). The molecule Pt6Cl12 shows the (trigonally elongated) structure of the classic M6X12 cluster compounds with (distorted) square‐planar PtCl4 fragments, however without metal‐metal bonds. The Pt atoms are shifted outside the Cl12 cuboctahedron by Δ = +0.046Å ( (Pt—Cl) = 2.315Å; (Pt—Pt) = 3.339Å). The scalar relativistic DFT calculations results in the full symmetry for the optimized structure of the isolated molecule with d(Pt—Cl) = 2.381Å, d(Pt—Pt) = 3.468Å and Δ = +0.072Å. The electron distribution of the Pt‐Pt antibonding HOMO exhibits an outwards‐directed asymmetry perpendicular to the PtCl4 fragments, that plays the decisive role for the cluster packing in the crystal. A comparative study of the Electron Localization Function with the hypothetical trans‐(Nb2Zr4)Cl12 molecule shows the distinct differences between Pt6Cl12 and clusters with metal‐metal bonding. Due to the characteristic electronic structure, the crystal structure of Pt6Cl12 in space group is an optimal one, which results from comparison with rhombohedral Zr6I12 and a cubic bcc arrangement.  相似文献   

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