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Coincidence ion pair production (cipp) spectroscopy of diiodine
Coincidence ion pair production (I + + I − ) (cipp) spectra of I 2 were recorded in a double imaging coincidence experiment in the one-photon excitation region of 71 600–74 000 cm −1 . The I + + I − coincidence signal shows vibrational band head structure corresponding to iodine molecule Rydberg states crossing over to ion-pair (I + I − ) potential curves above the dissociation limit. The band origin ( ν 0 ), vibrational wavenumber ( ω e ) and anharmonicity constants ( ω e x e ) were determined for the identified Rydberg states. The analysis revealed a number of previously unidentified states and a reassignment of others following a discrepancy in previous assignments. Since the ion pair production threshold is well established, the electric field-dependent spectral intensities were used to derive the cutoff energy in the transitions to the rotational levels of the 7pσ(1/2) ( v ′ = 3) state.
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Publication Date:
NSF-PAR ID:
10382705
Journal Name:
Physical Chemistry Chemical Physics
Volume:
24
Issue:
29
Page Range or eLocation-ID:
17569 to 17576
ISSN:
1463-9076
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