Vibrational spectra of penta-atomic silicon–carbon clusters. II. Linear Si2C3

Abstract

Fourier transform infrared matrix measurements carried out in conjunction with ab initio calculations reported in a companion paper by Rittby have resulted in the first identification of two fundamental vibrations, the C=C stretching mode ν3(σu)=1955.2 cm−1, and the Si–C stretching mode ν4(σu)=898.9 cm−1, of the SiC3Si cluster formed by trapping the products of the vaporization of silicon/carbon mixtures in Ar at 10 K. The observed frequencies, relative intensities, and 13C, 29Si, and 30Si isotopic shifts for the ν3 and ν4 vibrations are in good agreement with the results of the ab initio calculations at the second-order many-body perturbation theory [MBPT(2)] level which predict a linear centrosymmetric geometry for the ground state of SiC3Si. The results of force constant adjustment calculations are consistent with the proposed vibrational assignments and structure.

Vibrational spectra of penta-atomic silicon–carbon clusters. III. Pentagonal Si3C2

“…10 In Fourier transform infrared ͑FTIR͒ matrix studies in solid argon conducted in this laboratory the 1 ͑ ϩ ͒ϭ2080.1 cm Ϫ1 band of linear SiC 4 has been identified 9 as well as the 3 ͑ u ͒ϭ1955.2 and 4 ͑ u ͒ϭ898.9 cm Ϫ1 fundamentals of linear Si 2 C 3 . 8 In both cases the excellent agreement of measured frequencies, intensities, and isotopic shifts with the results of previously published ab initio calculations for SiC 4 , 11 and new calculations 7 carried out in conjunction with the experimental work for Si 2 C 3 , were crucial to the identification of the vibrational fundamentals. Recently the matrix results guided searches in the gas phase by Saykally and co-workers which resulted in high precision measurements using infrared diode laser spectroscopy of 1 ϭ2095.458 06 cm Ϫ1 for SiC 4 ͑Ref.…”

Study of absorption spectra and (hyper)polarizabilities of SiCn and SinC (n=2–6) clusters using density functional response approach

“…Experimental studies are mainly carried out by optical absorption spectroscopy, 4-13 mass spectrometry ͑MS͒, 14,15 and photoelectron spectroscopy. 16,17 From Fourier-transform infrared ͑FTIR͒ studies, a series of small SiC clusters with the following geometries have been identified: triangular SiC 2 , 7,11 rhomboidal Si 3 C, 9 rhombic Si 2 C 2 , 5 linear SiC 4 , 13 linear Si 2 C 3 , 8 pentagonal Si 3 C 2 , 10 and linear Si 2 C 4 . 6 The visible absorption spectrum 11,12 of SiC 2 shows a strong absorption peak at ϳ490 nm.…”

An MRD-CI study of the electronic spectrum of Si3C3

“…An excellent overview of the structure and bonding in mixed silicon carbon clusters up to eight atoms is given by Hunsicker and Jones [4]. In addition, Rittby, Graham, and Presilla-Marquez performed combined experimental [18][19][20] and theoretical [10,11] studies. Their extensive work led to the experimental detection of many small silicon-carbon clusters.…”