title: Identification of forbidden transitions in the nu(4) band of (14)NH(3) by intracavity laser-Stark spectroscopy.
abstract: Numerous perturbation-allowed transitions in the 6-microm nu(4) NH(3) band are assigned by laser-Stark spectroscopy. The transitions are forbidden in the sense that they follow the rules DeltaK = +/-2, a ? s, in contrast to the allowed transitions in nu(4), which follow the rules DeltaK = +/-1, a ? a, s ? s. These lines indicate the presence of a significant perturbation, which should be included in the analysis of nu(4) and which, through combination relations with allowed transitions, will provide a basis for precisely determining K-dependent energy intervals in NH(3).
authors.forename: W H
authors.initials: WH
authors.lastname: Weber
authors.forename: E A
authors.initials: EA
authors.lastname: Cohen