The X̃ 2A1 and Ã 2E states of the MgCH3 radical have been studied with correlation consistent basis sets and the coupled cluster method RCCSD(T) in order to compare with two recent experimental efforts [M. A. Anderson and L. M. Ziurys, Astrophys. J. 452, L157 (1995); R. Rubino, J. M. Williamson, and T. A. Miller, J. Chem. Phys. 103, 5964 (1995)]. The best computed values [RCCSD(T)/cc-pCVTZ] for the X̃ 2A1 state are (experimental results in parentheses): Ae=160.433 GHz, Be=10.948 GHz (B0=11.008 GHz), and μe=1.011 D. The Mg-CH3 bond is weak, 26.3 kcal/mol. Values for the Ã 2E state are Ae=154.648 GHz (A0=149.666 GHz), Be=10.87 GHz (B0=10.932 GHz), and μe=1.022 D. The excitation energy (Te) for the Ã 2E←X̃ 2A1 transition is 19 999 cm-1 (T00=20 030 cm-1). A brief discussion of bonding trends in Mg-containing radiais is included.
ASJC Scopus subject areas
- Physics and Astronomy(all)
- Physical and Theoretical Chemistry