Kristallstrukturen, Schwingungsspektren und Normalkoordinatenanalyse von cis- und trans-[ReCl4 (NCSe)(SeCN)]2- / Crystal Structures, Vibrational Spectra, and Normal Coordinate Analysis of cis- and trans-[ReCl4 (NCSe)(SeCN)]2-

1999 ◽  
Vol 54 (3) ◽  
pp. 357-362 ◽  
Author(s):  
S. Strueß ◽  
W. Preetz

The crystal structures of cis-(n-Bu4N)2[ReCl4(NCSe)(SeCN)] (monoclinic, space group P21/n a = 10.794(3), b = 11.687(3), c = 35.716(4) Å, β = 96.97(1)°, Z = 4) and trans- (CH2Py2)[ReCl4(NCSe)(SeCN)] (monoclinic, space group P21/c, a = 8.348(2), b = 7.518(1), c - 31.295(7) Å, ß = 97.12(2)°, Z = 4) have been determined by single crystal X-ray diffraction analysis. Based on the molecular parameters of the X-ray determinations the low temperature (10 K) IR and Raman spectra of the (n-Bu4N) salts have been assigned by normal coordinate analysis. The valence force constants are fd(ReN) = 1.68 and fd(ReSe) =1.15 mdyn/Å.

1998 ◽  
Vol 53 (11) ◽  
pp. 1329-1334 ◽  
Author(s):  
L. Homolya ◽  
S. Strueß ◽  
W. Preetz

The crystal structures of cis-(n-Bu4N)2[ReCl4(NCS)2] (triclinic, space group P1̅, a = 11,245( 1), b = 20.174(3), c = 21.320(8) Å, a =109.06(2), β = 96.46(2), γ = 98.22(5)°, Z = 4) and cis-(Ph4P)2[ReCl4(NCSe)2]·2CH2Cl2 (triclinic, space group P1̅, a = 10.341(2), b = 13.436(3), c = 19.616(4) Å, α = 92.70(2), β = 92.02(2), γ = 89.99( 1)°, Z= 2) have been determined by single crystal X-ray diffraction analysis. Both ambidentate ligands NCS and NCSe are bonded via the N atom. Using the molecular parameters of the X-ray determinations the low temperature (10 K) IR and Raman spectra of the (n-Bu4N) salts have been assigned by normal coordinate analysis based on a modified valence force field. The valence force constants fd(ReN) are 1,78(NCS) and 1,79(NCSe) mdyn/ Å.


1999 ◽  
Vol 54 (10) ◽  
pp. 1222-1228 ◽  
Author(s):  
S. Strueß ◽  
W. Preetz

By treatment of fac-[ReCl3I3]2- with (SeCN)2 indichloromethane fac-[ReCl3(NCSe)3]2- (1), mer-[ReCl3(NCSe)2cis (SeCN)]2- (2) and mer-[ReCl3I(NCSe)2cis]2- (3) are formed which have been separated by ion exchange chromatography on diethylaminoethyl cellulose. The crystal structures of mer-(Ph-P)2[ReCl3(NCSe)2cis(SeCN)] (triclinic, space group Pl̅, a = 16.099(1), b = 16.729(3), c =21.026(2) Å, α = 70.194(10), ß = 73.958(10), γ = 83.929(10)°, Z = 4) and mer-(n-Bu4N)2[ReCl3|(NCSe)2cis] (monoclinic, space group P21/c, a = 11.838(1), b = 12.796(2), c = 30.767(2) Å, ß = 97.419(6)°, Z = 4) have been determined by single crystal X-ray diffraction analysis. Based on the molecular parameters of the X-ray determinations the low temperature (10 K) IR and Raman spectra of the (n-Bu4N) salts have been assigned by normal coordinate analysis. The valence force constants are fd(ReN) = 1.79 (1), 1.71 (2), 1.71 (3) and fd(ReSe) = 1.15 (2) mdyn/Å.


1998 ◽  
Vol 53 (8) ◽  
pp. 823-828 ◽  
Author(s):  
A. Strueß ◽  
W. Preetz

Abstract The crystal structures of trans-(Ph4P)2[OsO2(ox)2] (monoclinic, space group P21/n, a = 12.281(2), b = 14.5440(13), c = 13.9810(12) Å, β = 100.000(8)°, Z = 2) and trans- (n-Bu4N)2[OsO2(mal)2] (triclinic, space group P1̄, a = 10.365(4),b = 10.707(3), c - 11.473(5) A, a = 73.00(2), β = 64.44(3), 7 = 82.55(3)°, Z = 1) have been determined by single crystal X-ray diffraction analysis. The IR and Raman spectra of these complexes were measured at room temperature. Based on the molecular parameters of the X-ray determinations normal coordinate analyses have been performed and the vibrations assigned. The valence force constants of [OsO2(ox)2]2- are fd(Os=O) = 6.7, fd(Os-O) = 2.9, fd(C-O) = 5.05, fd(C=O) = 11.2 and fd(C-C) = 4.7 mdyn/Å and of [OsO2(mal)2]2- fd(Os=O) = 6.7, fd(Os-O) = 2.9, fd(C-O) = 4.86, fd(C=O) =11.1 and fd(C-C) = 4.07 mdyn/Å.


2000 ◽  
Vol 55 (2) ◽  
pp. 178-184 ◽  
Author(s):  
L. Homolya ◽  
W. Preetz

The crystal structures of cis-(n-Bu4N)2[ReBr4(NCS)2] (1) (triclinic, space group P1̄, a = 11.475(6), b = 20.096(16), c = 22.144(11) Å, α = 110.56(6), β = 92.97(5), γ = 99.77(7)°, Z = 4), cis-(n-Bu4N)2[ReBr4(NCS)2] (2) (triclinic, space group P1̄, a = 11.527(3), b = 20.237(7), c = 22.07(2) Å, α = 110.05(4), β = 93.86(6), γ = 99.49(4)°, Z = 4) and cis-{n- Bu4N)2[ReBr4(NCS)(NCSe)] (3) (triclinic, space group P1̄, a = 11.488(2), b = 20.164(6), c = 22.158(5) Å, α = 110.44(2), β = 93.34(2), γ = 99.626(18)°. Z = 4) have been determined by single crystal X-ray diffraction analysis. Based on these molecular parameters the low temperature (10 K) IR and Raman spectra of the (n-Bu4N) salts have been assigned by normal coordinate analysis. The valence force constants are fd(ReN) = 1.70 (1), 1.70 (2) and 1.72 (3), fd(ReBr) = 1.36 (1), 1.30 (2) and 1.36 mdyn/Å (3).


1999 ◽  
Vol 54 (8) ◽  
pp. 1009-1014 ◽  
Author(s):  
L. Homolya ◽  
W. Preetz

The crystal structures of cis-(n-Bu4N)2[ReBr4(NCS)(SCN)] (1) (monoclinic, space group P21/n, a = 11.203(3), b = 11.738(5), c = 35.218(7) Å, β = 93.434(4)°, Z = 4), trans-(n-Bu4N)2[ReBr4(NCS)(SCN)] (2) (monoclinic, space group P21/n, a = 11.644(7), b = 13.695(3), c = 29.028(8) Å, β = 95.96(4)° Z = 4) and trans-(n-Bu4N)2[ReBr4(NCSe)(SeCN)] (3) (monoclinic, space group P21/n, a = 11.894(2), b = 13.737(2), c = 28.869(7) Å, β = 96.98(10)° Z = 4) have been determined by single crystal X-ray diffraction analysis. Based on these molecular parameters the low temperature (10 K) IR and Raman spectra of the (n-Bu4N) salts have been assigned by normal coordinate analysis. The valence force constants are fd(ReN) = 1.70 (1), 1.75 (2) and 1.75 (3), fd(ReS) = 1.32 (1) and 1.37 (2) and fd(ReSe) = 1.20 mdyn/Å (3).


1999 ◽  
Vol 54 (6) ◽  
pp. 767-771 ◽  
Author(s):  
L. Homolya ◽  
S. Strueß ◽  
W. Preetz

The crystal structures of trans-(n-Bu4N)2[ReCl4I(NCS)] (triclinic, space group P1, a = 11.268(3), b = 11.696(2), c = 18.109(3) A, a = 98.68(2) β = 106.40(2), γ= 97.58(2)°, Z = 2)and trans-(n-Bu4N)2 [ReCl4I(NCSe)] (orthorhombic, space group P212121 a = 11.839(2), b = 12.2679( 10), c = 31.136(5) A, Z = 4) have been determined by single crystal X-ray diffraction analysis. Based on the molecular parameters of the X-ray determinations the low temperature (10 K) IR and Raman spectra o f the (n-Bu4N) salts have been assigned by normal coordinate analysis. The valence force constants are fd(ReN) = 1.69(NCS) and 1.65(NCSe) mdyn/Å


1995 ◽  
Vol 50 (5) ◽  
pp. 772-780 ◽  
Author(s):  
J. Baurmeister ◽  
A. Franken ◽  
W. Preetz

Abstract By treatment of protonated monoalkyl-closo-hexaborates [B6H6R]-. R = CH3, C2H5, n-C3H7, i-C3H7 in aqueous alkaline solution with [As(C6H5)4]Cl the yellow orange deprotonated tetraphenylarsonium salts are precipitated, which react with methyl iodide or ethyl iodide to give dialkylated and protonated B6-compounds. The cisltrans isomers formed in a 1:1 ratio have been separated by ion exchange chromatography on diethylam inoethyl cellulose. Repeated deprotonation and reaction with methyl iodide affords mer-[B6H4 (CH3)3]-. The crystal structures of cis-[P(C6H5)4][B6H5(CH3)2] (I), trans-[P(C6H5)4][B6H5(CH3)2] (II) and mer-[P(C6H5)4][B6H4(CH3)3](III) have been determined by single crystal X-ray diffraction analyses; I and II are monoclinic, space group P2/n, I with a = 11.8690(5), b = 7.2575(7), c = 15.8689(3) Å , β = 111.454(17)°; II with a = 13.2853(7), b = 7.4608(8), c = 13.3549(11), β = 93.5(11); III is tetragonal, space group P4/n with a = 13.363(2), c = 7.5051(13). The three methyl substituents are statistically distributed over four equatorial positions of the B6 cage. The 11B NMR spectra of the di- and trialkylated com pounds exhibit shifts of ipso-B atoms to lower, of antipodal-B atoms to higher field compared with [B6H7]-. The IR and Raman spectra of the di- and trimethyl derivatives are similar to those of monom ethylhexaborate.


1997 ◽  
Vol 52 (3) ◽  
pp. 315-322 ◽  
Author(s):  
W. Preetz ◽  
A. Krull

Abstract The crystal structures of [(C5H5N)2CH2][OsCl4(ox)] (monoclinic, space group I2/m, a = 10.260(5), b = 13.841(5), c = 12.273(5) Å, β = 92.050(5)°, Z = 4), [(C5H5N)2CH2][OsBr4(ox)]·H2O(monoclinic, space group P21/n, a = 11.666(3),b = 11.591(5), c = 14.926(2) Å, β = 102.45(2)°, Z = 4) and [P(C6H5)4]2 [OsI4(ox)]·2CH2Cl2 (triclinic, space group P1̄, a = 14.597(2), b = 11.9185(9), c = 22.5624(14) Å, α = 80.284(8), β = 78.903(8), γ = 69.432(8)°, Z = 2) have been determined by single crystal X-ray diffraction analysis. The IR and Raman spectra of the three complexes were measured at room temperature. Using the molecular parameters of the X-ray determinations normal coordinate analyses based on a modified valence force field have been performed and the normal modes of vibration are assigned. With a set of 25 force constants and taking into account the innerligand vibrations a good agreement between observed and calculated frequencies has been achieved. The valence force constants of the X-Os-X axis are fd(OsCl) = 1.77, fd(OsBr) = 1.48, fd(OsI) = 1.0 mdyn/Å, of the X′-Os-O• axes are fd(OsCl′) = 1.88, fd(OsBr′) = 1.6, fd(OsI′) =1.1 mdyn/Å and fd(OsO•) ranges from 2.7 to 2.8 mdyn/Å.


1997 ◽  
Vol 50 (9) ◽  
pp. 903 ◽  
Author(s):  
Trevor W. Hambley ◽  
Walter C. Taylor ◽  
Stephen Toth

Four novel norditerpenoids were isolated from a new encrusting sponge, conveniently labelled Aplysilla pallida. The structures of aplypallidenone (1), aplypallidoxone (2), aplypallidione (3) and aplypallidioxone (4) were elucidated by spectroscopic studies and the crystal structures of aplypallidenone and aplypallidoxone have been determined by X-ray diffraction methods. The structure of (1) was refined to a residual of 0·040 for 1665 independent observed reflections and the structure of (2) was refined to a residual of 0·031 for 1699 independent observed reflections. The crystals of (1) are orthorhombic, space group P212121, a 7·728(2), b 10·838(4), c 24·880(5) Å, Z 4. Those of (2) are monoclinic, space group C 2, a 23·927(7), b 6·674(2), c 14·033(3) Å, Z 4.


Author(s):  
Michel Fleck ◽  
Ekkehart Tillmanns ◽  
Ladislav Bohatý ◽  
Peter Held

AbstractThe crystal structures of eight different L-malates have been determined and refined from single-crystal X-ray diffraction data. The compounds are the monoclinic (space groupIn addition, for all the compounds, powder diffraction data were collected, analysed and submitted to the powder diffraction file (PDF).


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