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1.
Preparation, Crystal Structures, Vibrational Spectra, and Normal Coordinate Analysis of trans-(PNP)[TcCl4(Py)2] and trans-(PNP)[TcBr4(Py)2] By reaction of (PNP)2[TcX6] with pyridine in the presence of [BH4]? (PNP)[TcX4(Py)2], X = Cl, Br, are formed. X-ray structure determinations on single crystals of these isotypic TcIII complexes (monoclinic, space group P21/n, Z = 2, for X = Cl: a = 13.676(4), b = 9.102(3), c = 17.144(2) Å, β = 91.159(1)°; for X = Br: a = 13.972(2), b = 9.146(3), c = 17.285(4) Å, β = 90.789(2)°) result in the averaged bond distances Tc? Cl: 2.386, Tc? Br: 2.519, Tc? N: 2.132(3) (X = Cl) and 2.143(4) Å (X = Br). The two pyridine rings are coplanar and vertical to the X? Tc? X-axes, forming angles of 42.28° (X = Cl) and 43.11° (X = Br). Using the molecular parameters of the X-ray structure determination and assuming D2h point symmetry, the IR and Raman spectra are assigned by normal coordinate analysis based on a modified valence force field. Good agreement between observed and calculated frequencies is obtained with the valence force constants fd(TcCl) = 1.45, fd(TcBr) = 1.035, fd(TcN) = 1.37 (X = Cl) and 1.45 mdyn/ Å (X = Br), respectively.  相似文献   

2.
Crystal Structures, Vibrational Spectra, and Normal Coordinate Analyses of the Stereoisomeric Trifluorotrichloroplatinates(IV), fac-[(C5H5N)2CH2][PtF3Cl3] · 0.5(CH3)2CO and mer-[(C5H5N)2CH2][PtF3Cl3] The geometric isomers fac- und mer-[PtF3Cl3]2? have been isolated by ion exchange chromatography on diethylaminoethyl cellulose. The doubly charged complex anions form stable AB-type salts with the dication dipyridiniomethane, [(C5H5N)2CH2]2+. The X-ray structure determination on single crystals of fac-[(C5H5N)2CH2][PtF3Cl3] · 0,5(CH3)2CO ( 1 ) (triclinic, space group P1 with a = 8.468(3), b = 8.847(2), c = 12.1260(10) Å, α = 79.986(12), β = 79.009(12), γ = 69.20(3)°, Z = 2) and mer-[(C5H5N)2CH2][PtF3Cl3] ( 2 ) (monoclinic, space group P21/n with a = 9.620(2), b = 14.031(4), c = 10.435(3) Å, β = 97.54(2)°, Z = 4) reveals the perfect ordering of the anion sublattice. Due to the stronger trans influence of Cl compared to F in asymmetric axes $ {\rm F}^. $? Pt? Cl′ the Pt? $ {\rm F}^. $ distance is lengthened by 1.8%, the Pt? Cl′ distance is shortened by 1.2% in comparison with symmetrically coordinated axes. Correspondingly, the vibrational spectra exhibit shifts of the Pt$ {\rm F}^. $ streching vibrations by 8% to lower, and of the PtCl′ streching vibrations by 12% to higher frequencies. Normal coordinate analyses performed on the basis of the X-ray data result in valence force constants for weakened Pt? $ {\rm F}^. $ bonds to be 14% lower, for the strengthened Pt? Cl′ bonds to be 20% higher than in symmetric axes, respectively. Generally the trans influence in fluorochloroplatinates(IV) on the bond lengths is very low with 1–2%, it results in considerable shifts of the stretching vibrations by 8–12% and reveals the strongest effect on the valence force constants with 14–20%.  相似文献   

3.
Crystal Structures, Vibrational Spectra, and Normal Coordinate Analysis of cis -(Et4N)[OsF2Cl4] and trans -(Ph4P)[OsF2Cl4] By oxidation of the pure fluorochloroosmates(IV) with KBrF4 or PbO2/trifluoracetic acid in dichloromethane the mixed pentavalent complex anions cis-[OsF2Cl4] and trans-[OsF2Cl4] are formed. X-ray structure determinations on single crystals have been performed of cis-(Et4N) · [OsF2Cl4] ( 1 ) (monoclinic, space group P21/n, a = 7.519(2), b = 17.648(2), c = 11.942(4) Å, β = 105.98(2)°, Z = 4) and trans-(Ph4P)[OsF2Cl4] ( 2 ) (tetragonal, space group P4/n, a = 12.677(2), c = 7.743(1) Å, Z = 2). Based on the molecular parameters of the X-ray determinations and assuming C2v point symmetry for the anion of 1 and D4h point symmetry for the anion of 2 the IR and Raman spectra have been assigned by normal coordinate analysis. Due to the stronger trans influence of chlorine as compared with fluorine for F · –Os–Cl′ axes significally different valence force constants are observed in comparison with symmetrically coordinated axes: fd(OsF · ) = 3.35, fd(OsF) = 3.73, fd(OsCl′) = 2.05 and fd(OsCl) with 1.98 and 2.00 mdyn/Å.  相似文献   

4.
Crystal Structure, Vibrational Spectrum, and Normal Coordinate Analysis of (PNP)2[ReFBr5] · H2O From the complex mixture obtained by oxidative ligand exchange of [ReBr6]2– with BrF3 [ReFBr5]2– has been isolated by ion exchange chromatography on diethylaminoethyl cellulose with 45% yield. The X-ray structure determination of (PNP)2[ReFBr5] · H2O (monoclinic, space group P21/c with a = 21.498(2), b = 13.314(3), c = 23.945(2) Å, β = 105.235(7)°, Z = 4) reveals a completely ordered anion sublattice resulting from the solvent water linked to the F ligand by a hydrogen bond (O–F: 2.758(6) Å). Due to the stronger trans influence of Br compared with F on the F · –Re–Br′ axis the Re–Br′ distance is shortened by 0.6% with regard to symmetrically coordinated axes. Based on the molecular parameters of the X-Ray determination the low temperature (10 K) IR and Raman spectrum of the (Me4N) salt is assigned by a normal coordinate analysis. The strengthening of the Re–Br′ bond due to the trans influence is indicated by an increase of the valence force constant fd(ReBr′) = 1.43 by 8% as compared with fd(ReBr) = 1.32 mdyn/Å of symmetric axes.  相似文献   

5.
Preparation, Vibrational Spectra, Normal Coordinate Analysis, and Crystal Structure of fac-(PPN)2[ReClBr2I3] By treatment of cis-[ReBr2I4]2? with HCl fac-[ReClBr2I3]2? is formed beside other mixed complex ions of the Type [ReClkBrlIm]2?, k + l + m = 6, which have been separated by ion exchange chromatography on diethylaminoethyl cellulose. The X-ray structure determination on single crystals of (PPN)2[ReClBr2I3] (monoclinic, space group P21/c, a = 22.059(3), b = 13.569(2), c = 23.9679(2) Å, β = 106.194(4)°, Z = 4) reveals the complete ordering of the complex anions. Due to the different trans influence the bond lengths ReCl (2.39) and ReBr (2.50) are slightly increased, the average ReI distance (2.66 Å) is a little shortened as compared with corresponding homoleptic octahedral complexes. The well resolved low temperature (80 K) IR and Raman spectra exhibit rheniumhalogen stretching vibrations in characteristic regions. The assignment is confirmed by the normal coordinate analysis based on a general valence force field. Taking into account increments of the trans influence on the valence force constants of the structural groups an adjustment between calculated and observed frequencies within a few cm?1 is achieved.  相似文献   

6.
Synthesis, Crystal Structures, Vibrational Spectra, and Normal Coordinate Analyses of the Tetrahalogeno‐bis‐Pyridine‐Osmium(III) Complexes cis ‐( n ‐Bu4N)[OsCl4Py2] and trans ‐( n ‐Bu4N)[OsX4Py2], X = Cl, Br By reaction of (n‐Bu4N)2[OsX6], X = Cl, Br, with pyridine and (n‐Bu4N)[BH4] tetrahalogeno‐bis‐pyridine‐osmium(III) complexes are formed and purified by chromatography. X‐ray structure determinations on single crystals have been performed of cis‐(n‐Bu4N)[OsCl4Py2] ( 1 ) (triclinic, space group P1, a = 9.4047(9), b = 10.8424(18), c = 17.007(2) Å, α = 71.833(2), β = 81.249(10), γ = 67.209(12)°, Z = 2), trans‐(n‐Bu4N)[OsCl4Py2] ( 2 ) (orthorhombic, space group P212121, a = 8.7709(12), b = 20.551(4), c = 17.174(4) Å, Z = 4) and trans‐(n‐Bu4N)[OsBr4Py2] ( 3 ) (triclinic, space group P1, a = 9.132(3), b = 12.053(3), c = 15.398(2) Å, α = 95.551(18), β = 94.12(2), γ = 106.529(19)°, Z = 2). Based on the molecular parameters of the X‐ray structure determinations and assuming C2 point symmetry for the anion of 1 and D2h point symmetry for the anions of 2 and 3 the IR and Raman spectra are assigned by normal coordinate analysis. The valence force constants of 1 are in the Cl–Os–Cl axis fd(OsCl) = 1.58, in the asymmetrically coordinated N′–Os–Cl · axes fd(OsCl · ) = 1.45, fd(OsN′) = 2.48, of 2 fd(OsCl) = 1.62, fd(OsN) = 2.42 and of 3 fd(OsBr) = 1.39 and fd(OsN) = 2.34 mdyn/Å.  相似文献   

7.
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   

8.
Synthesis, Crystal Structure, and Vibrational Spectra of cis ‐(CH2Py2)[ReBr4Py2]2 · (CH3)2CO By reaction of (n‐Bu4N)2[ReBr6] with pyridine and (n‐Bu4N)BH4 in dichloromethane halogeno‐pyridine‐rhenium(III)complexes are formed and purified by chromatography. X‐ray structure determination on a single crystal has been performed of cis‐(CH2Py2)[ReBr4Py2]2 · (CH3)2CO (monoclinic, space group P21/c, a = 15.0690(9), b = 8.3337(8), c = 35.588(4) Å, β = 96.409(7), Z = 4). Based on the molecular parameters of the X‐ray structure determination and assuming C2 point symmetry for the anion cis‐[ReBr4Py2] the IR and Raman spectra are assigned by normal coordinate analysis. The valence force constants are in the Br–Re–Br axis fd(ReBr) = 1.49, in the asymmetrically coordinated N′–Re–Br · axes fd(ReBr · ) = 1.03 und fd(ReN′) = 2.52 mdyn/Å.  相似文献   

9.
Preparation, Vibrational Spectra, and Normal Cooordinate Analysis of mer-[OsCl3I(NCS)2c]2? and Crystal Structures of two Modifications of mer-(Ph4As)2[OsCl3I(NCS)2c] By treatment of cis-/trans-[OsCl4I2]2? or fac-[OsCl3I3]2? with (SCN)2 in dichloromethane mixtures of different linkage isomers are formed, from which mer-[OsCl3I(NCS)]2? has been isolated by ion exchange chromatography on diethylaminoethyl cellulose. With tetraphenylarsonium ions mer-(Ph4As)2[OsCl3I(NCS)2c] crystallizes in two different modifications. From acetone solution the high-temperature form α precipitates above ?10°C, the low-temperature form β below, ?65°C. The X-Ray structure determinations on single crystals of α-mer-(Ph4As)2[OsCl3I(NCS)2c] (triclinic, space group P 1 , a = 10.245(5), b = 11.690(5), c = 22.027(5) Å, α = 83.650(5)°, β = 85.734(5)°, γ = 72.566(5)°, Z = 2) and β-mer-(Ph4As)2[OsCl3I(NCS)2c] (triclinic, space group P 1 , a = 10.959(5), b = 11.122(5), c = 21.745(5) Å, α = 97.677(5)°, β = 92.339(5)°, γ = 104.712(5)°, Z = 2) reveal the ordering of the complex anions, which significantly differ in their geometry. The via N coordinated thiocyanate groups exhibit Os? N? C angles of 172.7° and 173.3° (α) and of 164.4° and 175.4° (β). Using the molecular parameters of the X-Ray determinations the low temperature (10 K) IR and Raman spectra of the (n-Bu4N) salt of the complex anion are assigned by a normal coordinate analysis based on a modified valence force field. The valence force constants are fd(OsN) = 1.66 and 1.64 mdyn/Å. Taking into account the trans influence a good agreement between observed and calculated frequencies is achieved.  相似文献   

10.
Synthesis, Crystal Structure, Vibrational Spectra, and Normal Coordinate Analysis of K2[OsCl5(CO)] · H2O The X-ray structure determination of K2[OsCl5(CO)] · H2O (monoclinic, space group P21/c a = 13.600(2), b = 7.122(1), c = 22.186(11) Å, β = 98.66(3)°, Z = 8) revealed two crystallographic independent bat very similar complex anions [OsCl5(CO)]2? with rough C4v point symmetry. Due to the stronger trans influence of the carbonyl group the bond lengths in the Cl? Os? CO axis Os? Cl = 2.449(2), 2.430(2) Å are langer as compared with the octahedron basis Os? Cl = 2.340-2.370 Å. The water of crystallization is coordinated to potassium (K? OH2 = 2.625-2.815 Å). Using the molecular parameters the IR and Raman spectra are assigned by normal coordinate analysis. The valence force constants are fd(CO) = 15.30, fd(OsC) = 3.88, fd(OsCl) = 1.81, fd(OsCl) = 1.36, fd(OH) = 7.65, 7.82, 7.79 mdyn/Å. The strengthening of the Os? C bond by stronger back donation of the OsIII(d5) complex in comparison with the isostructural OsIV (d4) compound is discussed.  相似文献   

11.
Preparation, Crystal Structures, Vibrational Spectra, and Normal Coordinate Analysis of the Linkage Isomeric Chlororhodanoiridates(III) trans-[IrCl2(SCN)4]3? and trans-[IrCl2(NCS)(SCN)3]3? By treatment of Na2[IrCl6] with NaSCN in 2N HCl the linkage isomers trans-[IrCl2(SCN)4]3? and trans-[IrCl2(NCS)(SCN)3]3? are formed which have been separated by ion exchange chromatography on diethylaminoethyl cellulose. X-ray structure determinations on single crystals of trans-(n-Bu4N)3[IrCl2(SCN)4] ( 1 ) (monoclinic, space group P21/a, a = 18.009(4), b = 15.176(3), c = 23.451(4) Å, β = 93.97(2)°, Z = 4) and trans-(Me4N)3[IrCl2(NCS)(SCN)3] ( 2 ) (monoclinic, space group P21/a, a = 17.146(5), b = 9.583(5), c = 18.516(5) Å, β = 109.227(5)°, Z = 4) reveal the complete ordering of the complex anions. The via S or N coordinated thiocyanate groups are bonded with Ir? S? C angles of 105.7–109.7° and the Ir? N? C angle of 171.4°. The torsion angles Cl? Ir? S? C and N? Ir? S? C are 3.6–53.0°. The IR and Raman spectra of ( 1 ) are assigned by normal coordinate analysis using the molecular parameters of the X-ray determination. The valence force constants are fd(IrS) = 1.52 and fd(IrCl) = 1.72 mdyn/Å.  相似文献   

12.
Crystal Structure, Vibrational Spectra, and Normal Coordinate Analysis of K2[IrCl5(NH3)] The X-ray structure determination of K2[IrCl5(NH3)] (orthorhombic, space group Pnma, a = 13.426(4), b = 10.015(2), c = 6.8717(7) Å, Z = 4) revealed the Cs point symmetry of the complex anion [IrCl5(NH3)]2? (Ir? Cl = 2.337–2.365, Ir? N = 2.067(10); N? H = 0.73–0.79 Å). Using the molecular parameters the IR and Raman spectra are assigned by normal coordinate analysis. The valence force constants are fd(NH) = 5.88, fd(IrN) = 2.66, fd(IrCl) = 1.68 mdyn/Å.  相似文献   

13.
Crystal Structures, Vibrational Spectra, and Normal Coordinate Analysis of ( n -Bu4N)2[ReBr5(NCS)] and ( n -Bu4N)2[ReBr5(NCSe)] The X-ray structure determinations on single crystals of (n-Bu4N)2[ReBr5(NCS)] ( 1 ) (monoclinic, space group P21/n, a = 10.9860(9), b = 11.6860(7), c = 35.551(3) Å, β = 91.960(9)°, Z = 4) and (n-Bu4N)2[ReBr5(NCSe)] ( 2 ) (monoclinic, space group P21/n, a = 11.0208(15), b = 11.7418(16), c = 35.621(12) Å, β = 92.003(18)°, Z = 4) reveal that the thiocyanate and the selenocyanate group are bonded with the Re–N–C angle of 168.5° ( 1 ) and 169.9° ( 2 ). Based on the molecular parameters of the X-ray determinations the IR and Raman spectra have been assigned by normal coordinate analysis. The valence force constants fd(ReN) are 1.81 ( 1 ) and 1.75 mdyn/Å ( 2 ).  相似文献   

14.
Crystal Structures and Vibrational Spectra of Tetrahalogenoacetylacetonatoosmates(IV), [OsX4(acac)]?, X ? Cl, Br, I By reaction of the hexahalogenoosmates(IV) with acetylacetone the tetrahalogenoacetylacetonatoosmates(IV) [OsX4(acac)]? (X = Cl, Br, I) are formed, which have been purified by chromatography and precipitated from aqueous solution as tetraphenylphosphonium (Ph4P) or cesium salts. X-ray structure determinations on single crystals have been performed of (Ph4P)[OsCl4(acac)] ( 1 ) (triclinic, space group P1 , a = 9.9661(6), b = 11.208(2), c = 13.4943(7) Å, α = 101.130(9), β = 91.948(6), γ = 96.348(8)°, Z = 2), (Ph4P)[OsBr4(acac)] ( 2 ) (monoclinic, space group P21/n, a = 9.0251(8), b = 12.423(2), c = 27.834(2) Å, β = 94.259(7)°, Z = 4) and (Ph4P)[OsI4(acac)] ( 3 ) (monoclinic, space group P21/c, a = 18.294(3), b = 10.664(2), c = 18.333(3) Å, β = 117.68(2)°, Z = 4). Due to the increasing trans influence in the series O < Cl < Br < I the Os? O. distances of O.? Cl? X′ axes are lengthened and the OsO. stretching vibrations are shifted to lower frequencies. The Os? X′ bond lenghts are shorter as compared with symmetrically coordinated X? Os? X axes.  相似文献   

15.
Preparation of Halogeno Pyridine Rhenates(III), [ReX6?n(Py)n](3?n)? (X = Br, Cl; n = 1?3) Crystal Structures of trans-[(C4H9)4N][ReBr4(Py)2], mer-[ReCl3(Py)3], and mer- [ReBr3(Py)3] The mixed halogeno-pyridine-rhenates(III), [ReX6?n(Py)n](3?n)? (X = Br, Cl), n = 1?3, have been prepared for the first time by reaction of the tetrabutylammoniumsalts (TBA)2[ReX6] (X = Br, Cl) in pyridine with (TBA)BH4 and separation by chromatography on Al2O3. Apart from the monopyridine complexes only the trans and mer isomers are formed from the bis-and tris-pyridine compounds. The X-ray structure determinations of the isotypic neutral complexes mer- [ReX3(Py)3] (monoclinic, space group P 21/n, Z = 4; for X = Cl: a = 9,1120(8), b = 12,5156(14), c = 15,6100(13) Å, β = 91,385(7)°; for X = Br: a = 9,152(5), b = 12,852(13), c = 15,669(2) Å, β = 90,43(2)°) reveal, due to the stronger trans influence of pyridine compared with Cl and Br, that the Re? X distances in asymmetric Py? Re? X3 axes with ReCl3 = 2,397 Å and ReBr3 = 2,534 Å are elongated by 1,3 and 1% in comparison with symmetric X1? Re? X2 axes with ReCl1 = ReCl2 = 2,367 Å and ReBr1 = 2,513 and ReBr2 = 2,506 Å, respectively. The Re? N bond lengths are roughly equal with 2,12 Å. Trans-(TBA)[ReBr4(Py)2] crystallizes triclinic, space group P1 , a = 9,2048(12), b = 12,0792(11), c = 15,525(2) Å, α = 95,239(10), β = 94,193(11), γ = 106,153(9)°, Z = 2. The unit cell contains two independent but very similar complex anions with approximate D2h(mmm) point symmetry.  相似文献   

16.
Synthesis and Spectroscopic Characterization of Fluorocarbonylosmates, Normal Coordinate Analysis and Crystal Structure of fac -[OsF3Br2(CO)]2– By treatment of (n-Bu4N)2[OsBr5(CO)] with TlF in C6H5CF3 fac-(n-Bu4N)2[OsF3Br2(CO)] is formed, from which salts with the cations (Et4N)+, (py2CH2)2+, Tl+ and Cs+ are obtainable. Oxidation of the by-product [OsF5(CO)]2– with Cl2 yields [OsF5(CO)] which 19F NMR spectrum reveals a quintet (δF = 89.9) and a dublet (43.5 ppm) in the ratio 1 : 4 with coupling constants 2JFF = 94.9 Hz. Simultaneously produced mer-[OsF3Cl2(CO)] exhibits in the high field region a triplet (δF = –70.4) and a dublet (–66.2 ppm) in the ratio 1 : 2 and 2JFF = 9.5 Hz. The X-ray structure determinations of fac-Tl2[OsF3Br2(CO)] ( 1 ) (monoclinic P21/n, a = 11.143(12), b = 11.654(4), c = 13.751(10) Å, β = 91.50(6)°, Z = 8) and fac-(py2CH2)[OsF3Br2(CO)] · 1/2(CH3)2CO ( 2 ) (triclinic, P 1, a = 8.432(1), b = 9.009(1), c = 12.402(2) Å, α = 80.30(1), β = 79.68(2), γ = 68.14(1)°, Z = 2) result in nearly Cs symmetry of the complex anion with bond lengths in the ranges Os–F = 1.98–2.08, Os–Br = 2.45–2.46, Os–C = 1.83–1.84, C–O = 1.10 – 1.17 Å. Using the molecular parameters of the X-ray determinations the IR spectra have been assigned by normal coordinate analysis. The valence force constants are fd(CO) = 15.4–15.7, fd(OsC) = 4.4–4.7, fd(OsF) = 2.4–2.7, fd(OsF˙) = 1.6–2.0, fd(OsBr) = 1.7–2.1 mdyn/Å.  相似文献   

17.
Crystal Structure of (Me4N)3[Ir(SCN)6], Vibrational Spectra and Normal Coordinate Analysis From a mixture of the linkage isomers [Ir(NCS)n(SCN)6–n]3–, n = 0–2, pure [Ir(SCN)6]3– has been isolated by ion exchange chromatography on diethylaminoethyl cellulose. The X-ray structure determination on a single crystal of (Me4N)3[Ir(SCN)6] (trigonal, space group R3, a = 14.838(2), c = 23.827(1) Å, Z = 6) reveals the presence of two crystallographically independent complex anions which C3i symmetry correlates with the cation/anion ratio 3 : 1. The thiocyanate ligands are exclusively S-coordinated with the average Ir–S distance of 2.384 Å and the Ir–S–C angle of 106.4°. The torsion angles S–Ir–S–C are 17.5 and 42.1°. The IR and Raman spectra of the (n-Bu4N) salt are assigned by normal coordinate analysis based on the molecular parameters of the X-ray determination. The valence force constant fd(IrS) is 1.57 mdyn/Å.  相似文献   

18.
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   

19.
Preparation of the Nonahalogenodiplatinates(IV), [Pt2X9]?, X ? Cl, Br Spectroscopic Characterization, Normal Coordinate Analysis, and Crystal Structure of (PPN)[Pt2Br9] On heating the tetrabutylammonium salts (TBA)2[PtX6], with trifluoroacetic acid the nonahalogenodiplatinates(IV) (TBA)[Pt2X9], with X ? Cl, Br are formed. The X-ray structure determination on (PPN)[Pt2Br9] (orthorhombic, space group Pca2, Z = 4) shows for the anions pairs of face-sharing octahedra with nearly D3h symmetry. The mean terminal and bridging Pt? Br bond lengths are determined to be 2.42 and 2.52 Å, respectively. The electrostatic interaction of the Pt atoms results in the Pt? Pt distance of 3.23 Å and an elongation as it has been forecasted by the MO scheme for d6 systems. Using the structural data a normal coordinate analysis based on a general valence force field for [Pt2Br9]? has been performed, revealing a good agreement of the calculated frequencies with the bands observed in the IR and Raman spectra. The stronger bonding of the terminal as compared to the bridging ligands is shown by the valence force constants, fa(Br1) = 1,55 > fd(Brb) = 0,93 mdyn/ Å.  相似文献   

20.
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   

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