Determination of Rotational Parameters of CH₃CN, CD₃CN and their Different Isotopic Species in the Ground and v₄ = 1 States

Abstract

The millimeter-wave rotational spectra of the symmetric top molecules CH₃CN, ¹³CH₃CN, CH₃¹³CN, CH₃C¹⁵N, CD₃CN , ¹³CD₃CN, CD₃¹³CN and CD₃C¹⁵N have been investigated again in their ground and v₄ = 1 states. The analysis of spectra and fitting the frequencies in these states give rotational parameters with higher accuracy compare with previous works. The parameter H_J = -0.107(96) mHz was determined for CH₃C¹⁵N for the first time.