Mohamed K A
Department of Physics, Aligarh Muslim University, Uttar Pradesh, India.
Spectrochim Acta A Mol Biomol Spectrosc. 2009 May;72(4):762-5. doi: 10.1016/j.saa.2008.11.010. Epub 2008 Nov 21.
A systematic study of the high-resolution spectrum of (13)C(2)H(2) in the 3microm spectral region shows Q branch features in five hot parallel bands. These bands are due to the nu(3)+nu(4) (Pi(u))<--nu(4) (Pi(g)), nu(3)+nu(5) (Pi(g))<--nu(5)(Pi(u)), nu(3)+2nu(4) (Delta(u))<--2nu(4)(Delta(g)), nu(3)+2nu(5) (Delta(u))<--2nu(5)(Delta(g)) and nu(3)+nu(4)+nu(5)(Delta(g))<--nu(4)+nu(5)(Delta(u)) transitions. Sub-Q-branches (Q(e<--f) and Q(f<--e))are found to be resolved in the first three hot bands. More than 70 Q branch lines have been assigned, spread over the five hot bands. We have applied separate linear least squares fit to the transition wavenumbers of each Q branch/sub-Q-branches, which have yielded values of band origins and rotational constants, in agreement with those derived from the analysis of the P and R branches in earlier work. The analysis of the sub-Q-branches have also provided values of the l-doubling constants. This is the first report on the observation of Q branch lines in Delta-Delta hot bands, in the FTIR spectrum of (13)C(2)H(2).
对13C2H2在3微米光谱区域的高分辨率光谱进行的系统研究表明，在五个热平行带中存在Q支特征。这些带归因于ν(3)+ν(4) (π(u))←ν(4) (π(g))、ν(3)+ν(5) (π(g))←ν(5)(π(u))、ν(3)+2ν(4) (δ(u))←2ν(4)(δ(g))、ν(3)+2ν(5) (δ(u))←2ν(5)(δ(g))以及ν(3)+ν(4)+ν(5)(δ(g))←ν(4)+ν(5)(δ(u))跃迁。在前三个热带中发现了亚Q支（Q(e←f)和Q(f←e)）。已确定了70多条Q支谱线，分布在五个热带中。我们对每个Q支/亚Q支的跃迁波数分别进行了线性最小二乘法拟合，得到了带起源和转动常数的值，与早期工作中对P支和R支分析得出的值一致。对亚Q支的分析还提供了l-双重常数的值。这是关于在13C2H2的傅里叶变换红外光谱中δ-δ热带中Q支谱线观测的首次报告。
