Perpendicular Bands of Allene and Allene-d4

Abstract

The distribution of intensity in the perpendicular bands of allene has been examined, taking into account the effect of the Coriolis interaction between the degenerate levels v₉ and v₁₀. The results indicate that in all the perpendicular bands of allene and allene‐d₄ the ^RQ₀ branch lies on a line which divides the band into two equal (or very nearly equal) areas. This has been used as a criterion for a new rotational assignment of these bands and the rotational constants A and ζ have been re‐evaluated. The present A values, together with Stoicheff's (reference 16) B values indicate that the CH bond length is 1.061 A and the HCH angle 116°.