Water on the sun: line assignments based on variational calculations.
The infrared spectrum of hot water observed in a sunspot has been assigned. The high temperature of the sunspot (3200 K) gave rise to a highly congested pure rotational spectrum in the 10-micrometer region that involved energy levels at least halfway to dissociation. Traditional spectroscopy, based on perturbation theory, is inadequate for this problem. Instead, accurate variational solutions of the vibration-rotation Schrödinger equation were used to make assignments, revealing unexpected features, including rotational difference bands and fewer degeneracies than anticipated. These results indicate that a shift away from perturbation theory to first principles calculations is necessary in order to assign spectra of hot polyatomic molecules such as water.
Polyansky
O L
OL
Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT, UK.
Zobov
N F
NF
Viti
S
S
Tennyson
J
J
Bernath
P F
PF
Wallace
L
L
D055598:Chemical Phenomena; D002627:Chemistry, Physical; D019445:Solar Activity; D016082:Solar System; D013055:Spectrophotometry, Infrared; D013696:Temperature; D014867:Water / Q000032:analysis* / Q000737:chemistry
D014867:Water