Theory of nuclear spin conversion in ethylene
arXiv:physics/0008083 · doi:10.1103/PhysRevA.63.062505
Abstract
First theoretical analysis of the nuclear spin conversion in ethylene molecules (13^CCH4) has been performed. The conversion rate was found equal approx. 3x10^{-4} 1/s*Torr, which is in qualitative agreement with the recently obtained experimental value. It was shown that the ortho-para mixing in 13^CCH4 is dominated by the spin-rotation coupling. Mixing of only two pairs of ortho-para levels were found to contribute significantly to the spin conversion.
20 pages, 5 eps figures