Spectroscopic study on the iodine molecule by a sequential threehyphen;photon excitation

摘要

A threehyphen;photon absorption technique which utilizes a visibleBthinsp;3Pgr;0+uminus;Xthinsp;1Sgr;+gtransition followed by a simultaneous twohyphen;photon absorption was applied to study an ionhyphen;pair state of molecular iodine. The derived molecular parameters wereTe=51thinsp;707 cmminus;1, ohgr;e=131 cmminus;1, andBe=0.021thinsp;90 cmminus;1for theFprime;(0+u) ionhyphen;pair state, which dissociates to Iminus;(1S)+I+(1D). The excitation of I2to a single rovibronic level of theFprime; state was achieved and its fluorescence spectrum showed two discrete band systems corresponding to the transitions to: (1) the ground state at higher vibrational levels; and (2) the weakly bound state (Te=19thinsp;286 cmminus;1, ohgr;e=64 cmminus;1, andre=3.65 Aring;) converging to the I(2P3/2)+I(2P1/2) products.