Hyperfine structure of CH 3OH

Hyperfine structure of the (0, 0, 1) - (1, 0, 1) transition of methanol has been investigated by beam absorption and of the ( J, 1, 3-) → ( J, 1, 3+) transitions for J = 2, 3, and 6 by beam-maser spectroscopy. The best-fit results for the spin-rotation and spin-spin coupling constants C _JKτ±⁽ⁱ⁾ and D _JKτ±⁽ⁱ⁾, respectively, are in kHz : C ₁₀₁⁽¹⁾ = 2.4(10) , C ₁₀₁⁽²⁾ = -0.6(10) , D ₁₀₁⁽¹⁾ = -13.8(9) , D ₁₀₁⁽²⁾ = 7.0(9) , C _213-⁽¹⁾ = -5.0(10) , C _213-⁽²⁾ = -5.5(10) and ( C _J13-⁽²⁾ - C _J13+⁽²⁾) = 0.98(9) .

The numbers within parentheses indicate the experimental error.