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1.
Preparation, Crystal Structures, Vibrational Spectra, and Normal Coordinate Analysis of Four Linkage Isomeric Tetrachlorodirhodanoosmates(IV) By treatment of cis- or trans-[OsCl4I2]2? with (SCN)2 in dichloromethane the linkage isomers cis-[OsCl4(NCS)2]2? ( 1 ), trans-[OsCl4(NCS)(SCN)]2? ( 2 ), cis-[OsCl4(NCS)(SCN)]2? ( 3 ) and trans-[OsCl4(SCN)2]2? ( 4 ) are formed which have been separated by ion exchange chromatography on diethylaminoethyl cellulose. The X-Ray structure determinations on single crystals of cis-(Ph4As)2[OsCl4(NCS)2] (triclinic, space group P1 , a = 10.019(5), b = 11.702(5), c = 21.922(5) Å, α = 83.602(5)°, β = 85.718(5)°, γ = 73.300(5)°, Z = 2), trans-(Ph4As)2[OsCl4 · (NCS)(SCN)] (monoclinic, space group P21/c, a = 18.025(5), b = 11.445(5), c = 23.437(5) Å, β = 94.208(5)°, Z = 4), cis-(Ph4As)2[OsCl4(NCS)(SCN)] (triclinic, space group P1 , a = 10.579(5), b = 11.682(5), c = 22.557(5) Å, α = 81.073(5)°, β = 85.807(5)°, γ = 87.677(5)°, Z = 2) and trans-(Ph4As)2 · [OsCl4(SCN)2] (triclinic, space group P1 , a = 10.615(5), b = 11.691(5), c = 11.907(5) Å, α = 111.314(5)°, β = 96.718(5)°, γ = 91.446(5)°, Z = 1) reveal the complete ordering of the complex anions. The via N or S coordinated thiocyanate groups are located nearly direct above one of the cis-positioned Cl ligands with Os? N? C angles of 171.2° and 174.3° ( 1 ), 162.3° ( 2 ), 172° ( 3 ) and Os? S? C angles of 108.3° ( 2 ), 105.7° ( 3 ) and 105.5° ( 4 ). Using the molecular parameters of the X-Ray determinations the low temperature (10 K) IR and Raman spectra of the (n-Bu4N) salts of all four linkage isomers are assigned by normal coordinate analyses based on a modified valence force field. The valence force constants are fd(OsN) = 1.59 ( 1 ), 1.67 ( 2 ), 1.60 ( 3 ) and fd(OsS) = 1.27 ( 2 ), 1.31 ( 3 ) and 1.32 mdyn Å?1 ( 4 ). Taking into account increments of the trans influence a good agreement between observed and calculated frequencies is achieved.  相似文献   

2.
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   

3.
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   

4.
Preparation, Crystal Structure and Normal Coordinate Analysis of Linkage Isomeric Pentachlororhodanoosmates(IV) By treatment of [OsCl5I]2? with (SCN)2 in dichloromethane the linkage isomers [OsCl5(NCS)]2? and [OsCl5(SCN)]2? are formed which have been separated by ion exchange chromatography on diethylaminoethyl cellulose. The X-ray structure determination on single crystals of (Ph4As)2[OsCl5(NCS)] (monoclinic, space group P21/a, a = 18.872(2), b = 11.6024(2), c = 22.786(1), β = 109.057(1)°, Z = 4) and (Ph4As)2[OsCl5(SCN)] (monoclinic, space group P21/a, a = 19.057(2), b = 11.306(2), c = 22.612(1), β = 106.64(2)°, Z = 4) reveals the complete ordering of the complex anions. The thiocyanate group is located above one of the Cl ligands of the equatorial plane with the Os? N? C angle of 166.1° for N bonding and the Os? S? C angle of 109.9° for S bonding. The IR and Raman spectra of both linkage isomers known from literature are assigned by normal coordinate analysis based on the general valence force field using the molecular parameters of the X-ray determination. The valence force constants are fd(OsN) = 1,81 and fd(OsS) = 1,32 mdyn/Å. Taking into account increments of the trans influence a good adjustment between observed and calculated frequencies is achieved.  相似文献   

5.
Preparation and Crystal Structure of (n-Bu4N)3[Ir(NCS)(SCN)5] The evaporated ethanolic extrakt of the reaction product of K3[IrCl6] and HNO3, refluxed with an aqueous KSCN solution yields a mixture of the linkage isomers [Ir(NCS)n(SCN)6?-n]3?, n = 0? 2, and small amounts of linkage isomeric chloropentarhodanoiridates(III), from which [Ir(NCS)(SCN)5]3? has been isolated by ion exchange chromatography on DEAE-cellulose. The X-Ray structure determination on a single crystal of (n-Bu4N)3[Ir(NCS)(SCN)5] (monoclinic, space group P 21/a, a = 17.513(5), b = 32.607(5), c = 23.661(5) Å, β = 94.757(5)°, Z = 8) confirms the existance of a heteroleptic hexakis(thiocyanato(N)-thiocyanato(S))iridate(III) with an Ir? N distance of 2.03 Å and Ir? S bond lengths between 2.29 and 2.38 Å. The SCN groups with angles between 166 and 175° are nearly linear with Ir? S? C angles from 99.9 to 109.4°. The Ir? N? C angles of the two crystallographic independent anions are 166 and 174°.  相似文献   

6.
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   

7.
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   

8.
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   

9.
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   

10.
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   

11.
Synthesis, Crystal Structures, Vibrational Spectra, and Normal Coordinate Analyses of the mer ‐Trihalogeno‐tris‐Pyridine‐Osmium(III) Complexes mer‐[OsX3Py3], X = Cl, Br, I By reaction of the hexahalogenoosmates(IV) with pyridine and iso‐amylalcohol mer‐trihalogeno‐tris‐pyridine‐osmium(III) complexes are formed and purified by chromatography. X‐ray structure determinations on single crystals have been performed of mer‐[OsBr3Py3] (monoclinic, space group P21/n, a = 9.098(5), b = 12.864(5), c = 15.632(5) Å, β = 90.216(5)°, Z = 4) and mer‐[OsI3Py3] (monoclinic, space group P21/n, a = 9.0952(17), b = 13.461(4), c = 15.891(10), β = 91.569(5)°, Z = 4). The pyridine rings are twisted propeller‐like against the N3 meridional plane with mean angles of 49° (Cl), 46° (Br), 44° (I). Based on the molecular parameters of the X‐ray structure determinations and assuming C2 point symmetry, the IR and Raman spectra are assigned by normal coordinate analysis. Due to the stronger trans influence of pyridine as compared with the halide ligands for N'–Os–X · axes significantly different valence force constants are observed in comparison with symmetrically coordinated octahedron axes: fd(OsCl) = 1.74, fd(OsCl·) = 1.49, fd(OsBr) = 1.43, fd(OsBr · ) = 1.18, fd(OsI) = 0.99, fd(OsI · ) = 0.96, fd(OsN) between 1.96 and 2.07 and fd(OsN') between 2.13 and 2.32 mdyn/Å.  相似文献   

12.
The reaction of Ph2P(S)N(SiMe3)2 with potassium tert-butoxide in a 1:1 molar ratio produces K[Ph2P(S)NSiMe3], which was converted to the AsPh4+ salt by metathesis with [AsPh4]Cl. The X-ray crystal structure of [AsPh4][Ph2P(S)NSiMe3] · 0.5 THF consists of noninteracting AsPh4+ and Ph2P(S)NSiMe3? ions with d(P? S) = 1.980(4) Å and d(P? N) = 1.555(8) Å. The PNSi bite angle in the anion is 136.3(5)°. Electrophilic attack by Ph2P(S)Cl occurs at the sulfur atom of Ph2P(S)NSiMe3?. The oxidation of the anion with iodine produces a disulfide which regenerates K[Ph2P(S)NSiMe2] upon treatment with potassium tert-butoxide.  相似文献   

13.
Preparation and Crystal Structure of Tetraphenylphosphonium Hexathiocyanatorhodate(III), [P(C6H5)4]3[Rh(SCN)6] By treatment of RhCl3 · n H2O with KSCN in water a mixture of the linkage isomers [Rh(NCS)n(SCN)6–n]3?, n = 0–2 is formed which is separated by ion exchange chromatography on diethylaminoethyl cellulose. The X-ray structure determination on a single crystal of [P(C6H5)4]3[Rh(SCN)6] (monoclinic, space group C1c1, a = 13.620(5), b = 22.929(13), c = 22.899(9) Å, β = 98.55(3)°, Z = 4) confirms the coordination of all ligands via S with the middle Rh? S distance of 2.372 Å and Rh? S? C angles of 109°. The SCN groups are nearly linear with 175° and averaged bondlengths S? C 1.63 and C? N 1.14 Å. The crystal lattice is build up by layers of complex anions and voluminous cations with no specific interactions but which are closely connected by thiocyanate ligands and phenyl rings.  相似文献   

14.
Synthesis and Crystal Structures of (Ph3PNPPh3)2[Re2Br10] and (Ph4P)[Re2Br9] Depending on the molar ratio by reaction of [n-Bu4N]2[ReBr6] with the Lewis acid BBr3 in dichloromethane the bioctahedral complexes [n-Bu4N]2[Re2Br10] and [n-Bu4N][Re2Br9] are formed. The X-ray structure determination on (Ph3PNPPh3)2[Re2Br10] (monoclinic, space group C 2/c, a = 20.007(4), b = 15.456(5), c = 24.695(4) Å, β = 107.53(2)°, Z = 4) reveals a centrosymmetric edge-sharing complex anion with approximate D2h symmetry and mean terminal and bridging Re–Br bond lengths of 2.453 (equatorial), 2.482 (axial) and 2.591 Å, respectively, and a Re–Re distance of 3.880 Å. (Ph4P)[Re2Br9] (triclinic, space group P 1, a = 11.062(2), b = 12.430(3), c = 13.163(5) Å, α = 72.94(2), β = 68.47(2), γ = 82.09(2)°, Z = 2) contains a confacial bioctahedral anion with nearly D3h symmetry and mean terminal and bridging Re–Br distances of 2.460 and 2.536 Å, respectively, and a Re–Re distance of 2.780 Å.  相似文献   

15.
Preparation and Spectroscopic Characterization of Bond-Isomeric Halogenorhodanoosmates(IV) By oxidation of tr.-[OsCl4BrI]2? or tr.-[OsCl4I2]2? with (SCN)2 in CH2Cl2, by substitution of [OsCl5I]2? with SCN? or [OsCl5(NCS)]2? with F? in toluene and by reaction of [OsF5Cl]2? with (SCN)2 in CH2Cl2 the following bondisomers are prepared: tr.-[OsF4Cl(NCS)]2?/tr.-[OsF4Cl(SCN)]2?, tr.-[OsFCl4(NCS)]2?/tr.-[OsFCl4(SCN)]2?, tr.-[OsCl4Br(NCS)]2?/tr.-[OsCl4Br(SCN)]2?, tr.-[OsCl4I(NCS)]2?/tr.-[OsCl4I(SCN)]2?,tr.-[OsCl4(NCS)2]2?/tr.-[OsCl4(NCS)(SCN) ]2?/tr.-[OsCl4(SCN)2]2?, [OsBr5(NCS)]2?/[OsBr5(SCN)]2? and tr.-[OsBr4(NCS)(SCN)]2?. All complexes are isolated as pure compounds by ion exchange chromatography on DEAE-cellulose. In the IR and Raman spectra νCN(S), νCS(N) and δNCS are found at higher wave numbers than νCN(N), νCS(S) and δSCN. According to spin orbit coupling and to lowered symmetry (D4h, C4v) the splitted intraconfigurational transitions are observed at 10 K as weak bands in the regions 600, 1000, 2000 nm. The O? O transitions are calculated from vibrational fine structure and in some cases are confirmed by electronic Raman bands with the same frequencies. The energy niveaus deduced with ζ(OsIV) = 3200 cm?1 and the calculated Racah parameters B are in good agreement with the barycenters of the observed multiplets for D4h and C4v symmetry.  相似文献   

16.
Crystal Structures, Normal Coordinate Analyses, and 15N NMR and 77Se NMR Chemical Shifts of trans ‐[OsO2(NCO)4]2–, trans ‐[OsO2(NCS)4]2–, and trans ‐[OsO2(SeCN)4]2– The crystal structures of trans‐(Ph3PNPPh3)2[OsO2(NCO)4] ( 1 ) (orthorhombic, space group Pbca, a = 19.278(3), b = 16.674(4), c = 19.982(2) Å, Z = 4), trans(n‐Bu4N)2[OsO2(NCS)4] ( 2 ) (triclinic, space group P1, a = 12.728(3), b = 12.953(3), c = 16.255(6) Å, α = 97.39(4), β = 105.62(2), γ = 95.25(3)°, Z = 2) and trans‐(n‐Bu4N)2[OsO2(SeCN)4] ( 3 ) (tetragonal, space group I4/m, a = 13.406(2), c = 12.871(1) Å, Z = 2) have been determined by single‐crystal X‐ray diffraction analysis, showing the bonding of NCO and NCS via the N atom but the coordination of SeCN via the Se atom to osmium. Based on the molecular parameters of the X‐ray determinations the vibrational spectra have been assigned by normal coordinate analyses. The valence force constants are for 1 fd(OsO) = 6.43, fd(OsN) = 3.32, fd(NC) = 14.50, fd(CO) = 12.80, for 2 fd(OsO) = 6.56, fd(OsN) = 1.75, fd(NC) = 15.00, fd(CS) = 5.50, and for 3 fd(OsO) = 6.75, fd(OsSe) = 0.99, fd(SeC) = 3.23, fd(CN) = 15.95 mdyn/Å. The observed NMR shifts are δ(15N) = –386.6 ( 1 ), δ(15N) = –294.7 ( 2 ) and δ(77Se) = 108.8 ppm ( 3 ).  相似文献   

17.
Synthesis, EPR and X-Ray Structure of mer-Trichloro(2,2′-bipyridine)nitridotechnetium(VI) — a new Technetium(VI) Nitrido Complex mer-Trichloro(2,2′-bipyridine)nitridotechnetium(VI) has been prepared by the reaction of (NBu4)[TcNCl4] with 2,2′-bipyridine in acetonitrile, whereas the same procedure gives in methanol the technetium(V) cation [TcNCl(bipy)2]+. The EPR spectrum of [TcNCl3(bipy)] suggests a meridional coordination of the three chloro ligands. [TcNCl3(bipy)] crystallizes monoclinic in the space group P21/n; a = 8.572(1), b = 15.462(1), c = 10.110(1) Å, β = 104.21(1)°, Z = 4. The R value converged at 0.034 on the basis of 3 040 reflections. The technetium atom is distorted octahedrally coordinated with the chloro ligands meridionally cis with respect to the nitrido nitrogen. The Tc? N(1) bond length is 1.669(4) Å, and the Tc? N(3) bond (2.371(4) Å) is significantly lengthened due to the structural trans labilizing influence of the “N3?” ligand.  相似文献   

18.
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   

19.
Novel Halogenochalcogeno(IV) Acids: [H3O(Benzo‐18‐Crown‐6)]2[Te2Br10] and [H5O2(Dibenzo‐24‐Crown‐8)]2[Te2Br10] Systematic studies on halogenochalcogeno(IV) acids containing tellurium and bromine led to the new crystalline phases [H3O(Benzo‐18‐Crown‐6)]2[Te2Br10] ( 1 ) and [H5O2(Dibenzo‐24‐Crown‐8)]2[Te2Br10] ( 2 ). The [Te2Br10]2‐ anions consists of two edge‐sharing distorted TeBr6 octahedra, the oxonium cations are stabilized by crownether. ( 1 ) crystallizes in the monoclinic space group P21/n with a = 14.520(5) Å, b = 22.259(6) Å, c = 16.053(5) Å, β = 97.76(3)° and Z = 4, whereas ( 2 ) crystallizes in the triclinic space group with a = 11.005(4) Å, b = 12.103(5) Å, c = 14.951(6) Å, α = 71.61(3)°, β = 69.17(3)°, γ = 68.40(3)° and Z = 1.  相似文献   

20.
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   

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