Absorption spectra of rotationally cold ammonia ((NH3)-N-14) molecules have
been recorded in the 6400-6630 cm(-1) region, using the cavity-enhanced ab
sorption technique in combination with a slit-nozzle expansion. Two perpend
icular rovibrational bands have been identified: the nu(1) + nu(3) band at
6609 cm(-1), and a 'new' band at 6557 cm(-1) which is tentatively assigned
to a transition into the \l\ = 2 component of the nu(1) + 2 nu(4) state. (C
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