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Transfer and storage of vibrational energy in liquids: Liquid carbon monoxide and its solutions with argon

1981; Elsevier BV; Volume: 54; Issue: 2 Linguagem: Inglês

10.1016/0301-0104(81)80238-8

1873-4421

David W. Chandler, George E. Ewing,

Advanced Thermodynamics and Statistical Mechanics

Abstract Liquid carbon monoxide and its solutions with argon in a five order of magnitude concentration range were vibrationally excited by pumping with a blackbody source. Infrared fluorescence decay from the excited carbon monoxide was used to explore the storage and transfer of vibrational energy in this system. In the limit of the infinitely dilute solution the storage time, 18 ms, is determined by IR spontaneous emission. For concentrations in the range 0.01–1 mole % this radiation tends to be trapped by CO self-absorption and the lifetime of the vibrational excitation lengthens. We apply a simple model to interpret this lifetime behavior. Neat carbon monoxide stores vibrational energy for 1 s. Here radiation trapping is so effective that vibrational energy is lost essentially by non-radiative processes. The 1 s lifetime allows a useful limit to be placed on the vibration to translation and rotation rate of relaxation of excited CO by its neighbors.