Showing papers on "Water cluster published in 1978"

Introduction to Polymolecular Water Clusters and their Infrared Activity.

Abstract: : This report is intended as a guide for electro-optical applications engineers interested in the effects of polymolecular clusters of water upon infrared transmission of the atmosphere. It is a compendium of work on the subject ranging from the oldest to the newest, some of which is not yet generally accepted by the scientific community. A theoretical model for infrared absorption spectra due to intermolecular hydrogen bonding is developed from a simple cluster model. Expressions leading to approximate values of hydrogen-bond strength are developed, allowing equations and curves to be derived, from data in the literature, for equilibrium cluster concentrations in moist air or water vapor, as functions of saturation ratio and temperature. The very large differences in absorptivity between water in the vapor and liquid phases are explained, as are 'pressure-squared' and inverse temperature dependencies of water cluster absorption in the infrared. Applications are suggested. (Author)