Die Schwingungsspektren der Silylanionen (SiH3)nSiH⊖3-n und (SiD3)nSiD⊖3-n / Vibrational Spectra of the Silyl Anions (SiH3)nSiH⊖3-n and (SiD3)nSiD⊖3-n

1974 ◽  
Vol 29 (9-10) ◽  
pp. 647-653 ◽  
Author(s):  
Hans Bürger ◽  
Reint Eujen

The IR and Raman spectra of SiH3⊖, SiH3SiH2⊖, (SiH3)2SiH⊖, (SiH3)3Si⊖ and their deuterated derivatives have been recorded in HMPT and HMPT-d18 solutions. Most normal vibrations have been identified. The SiH and SiSi stretching vibrations are considerably lower than for analogous silanes and silylphosphines, ∼ 2050 and 1850-1900 cm-1 being characteristic for SiH3 and SiH⊖n groups respectively. The assignments are proved by a normal coordinate analysis, and force constants have been calculated. The negative charge is mainly localized on the trivalent Si atom and the lone pair acts repulsively rather than strengthening the SiSi bond through (p→d)π effects.

1975 ◽  
Vol 30 (7-8) ◽  
pp. 539-543 ◽  
Author(s):  
Reinhard Demuth ◽  
Joseph Grobe ◽  
Robert Rau

The gas phase IR and liquid phase IR and Raman spectra of (CF3)2PMn(CO)5 and (CF3)2AsMn(CO)6 have been recorded. The spectra are assigned on the basis of a normal coordinate analysis using a transferred force field.


1990 ◽  
Vol 55 (6) ◽  
pp. 1485-1490 ◽  
Author(s):  
Peter Schwendt ◽  
Milan Sýkora

The infrared and Raman spectra of M2[V2O2(O2)4(H2O)]·xH2O and M2[V2O2(O2)4(D2O)]·xD2O (M = N(CH3)4, Cs) were measured. In the region of the vanadium-oxygen stretching vibrations, the spectra were interpreted based on normal coordinate analysis, employing empirical correlations between the bond lengths and force constants.


1981 ◽  
Vol 59 (19) ◽  
pp. 2909-2920 ◽  
Author(s):  
John E. Drake ◽  
Boris M. Glavinčevski ◽  
Layla N. Khasrou

Methylthiosilanes of the type (CH3)nH3−nSiSCH3, n = 0–3, and (CH3)HSi(SCH3)2 have been prepared. Their ir and Raman spectra were recorded and assigned. The assignments were supported by normal coordinate analyses based on a modified valence force field.


1971 ◽  
Vol 25 (2) ◽  
pp. 187-191 ◽  
Author(s):  
Edward Maslowsky ◽  
Kazuo Nakamoto

The ir and Raman spectra of CpTiCl3 and CP2MX2 (Cp = C5H5, M = Ti, Zr and Hf, and X = a halogen) type compounds have been measured. Approximate normal coordinate analyses have been carried out to assign the skeletal modes in the low frequency region.


1994 ◽  
Vol 49 (6) ◽  
pp. 753-758 ◽  
Author(s):  
P. Prillwitz ◽  
W. Preetz

The IR and Raman spectra of the ten bromo-iodo-rhenates(IV) [ReBrnI6-n]2-, n = 0 -6 , including the geometrical isomers for n - 2,3,4, have been recorded at 80 K. The vibrational spectra are completely assigned according to point groups Oh, D4h, C4v, C3v, and C2v, as supported by normal coordinate analyses based on a general valence force field. Due to the different mms-influences Br < I in asymmetric axes Br•-Re-I', the Re-I' bonds are strengthened and the Re-Br• bonds are weakened, as indicated by valence force constants, for Re-I' on average 8,5% higher and for Os-Br• 8,3% lower, as compared with the values calculated for symmetric I-Re-I and Br-Re-Br axes, respectively


1982 ◽  
Vol 60 (2) ◽  
pp. 174-189 ◽  
Author(s):  
J. J. C. Teixeira-Dias ◽  
V. M. Jardim-Barreto ◽  
Y. Ozaki ◽  
A. C. Storer ◽  
P. R. Carey

Infrared, Raman, and resonance Raman data are reported for ethyl and methyl dithioacetate together with data for their isotopically substituted analogs: CD3C(=S)SCH3, CH3C(=S)SCD3, 13CH3C(=S)SCH3, CH313C(=S)SCH3, CD3C(=S)SCH2CH3, CH3C(=S)SCD2CH3, and CH313C(=S)SCH2CH3. Based on these data and a normal coordinate analysis of methyl dithioacetate, assignments are proposed for the majority of bands appearing in the vibrational spectra. Using excitation wavelengths in the 324–356 nm region strong intensity enhancement is observed for Raman bands near 1195, 1100, 730, and 580 cm−1 which are assigned to stretching motions of the CCSSC skeleton. Raman excitation profiles are reported for the 1197 and 581 cm−1 bands of ethyl dithioacetate and the electronic absorbance peak near 305 nm is identified as the source of resonance Raman intensity enhancement.


2004 ◽  
Vol 82 (6) ◽  
pp. 987-997 ◽  
Author(s):  
P J.G Goulet ◽  
R F Aroca

In this work, surface-enhanced vibrational spectroscopy and normal vibrational spectroscopy as well as density functional theory (DFT) computational methods have been employed to investigate the nature of the chemical adsorption and orientation of the surface species generated from salicylic acid at silver surfaces. The structure of salicylic acid and its IR and Raman spectra are determined at the B3LYP/6-311+G(d,p) level of theory. These results are used in the assignment of the vibrational spectra. Surface-enhanced Raman scattering (SERS) spectra obtained from silver island films thinly coated with salicylic acid confirm chemical adsorption on the Ag nanostructures. To probe the nature of this surface complex, the optimized geometries and IR and Raman spectra of two model salicylate-silver complexes (Ag1 and Ag2) were calculated at the B3LYP/Lanl2DZ level of theory. It was found that good agreement exists between experimentally observed SERS spectra and the simulated SERS spectra of a complex with the salicylate monoanion bound to a Ag+ ion through its carboxylate group (Ag1). The carboxylate silver salt of salicylic acid (essentially the Ag1 complex) was also prepared, and its IR and Raman spectra were recorded for comparison with the surface-enhanced vibrational spectra. These results, along with the application of surface selection rules, suggest that salicylic acid is deprotonated at silver surfaces, interacting through its carboxylate group alone, and is preferentially in a tilted head-on orientation.Key words: chemisorption, salicylic acid, silver, density functional theory, surface-enhanced Raman scattering, reflection-absorption IR spectroscopy, surface-enhanced IR absorption.


Sign in / Sign up

Export Citation Format

Share Document