Desorption-induced evolution of cubic and hexagonal ices in an ultrahigh vacuum and cryogenic temperatures. Issue 41 (19th October 2021)

• Record Type: Journal Article
• Authors: Vishwakarma, Gaurav; Ghosh, Jyotirmoy; Pradeep, Thalappil
• Is Part Of: Physical chemistry chemical physics. Volume 23:Issue 41(2021)
• Page Start: 24052
• Page End: 24060
• Publication Date: 2021-10-19
• Subjects: Chemistry, Physical and theoretical -- Periodicals; 541.3
• DOI: 10.1039/d1cp03872a
• Languages: English
• ISSNs: 1463-9076

Abstract

Abstract : Reflection absorption infrared spectroscopic investigations of multilayer films of acetonitrile (ACN) and water in an ultrahigh vacuum under isothermal conditions showed the emergence of cubic (ice Ic ) and hexagonal (ice Ih ) ices depending on the composition of the film. Abstract : Reflection absorption infrared spectroscopic investigations of multilayer films of acetonitrile (ACN) and water in an ultrahigh vacuum under isothermal conditions showed the emergence of cubic (ice Ic ) and hexagonal (ice Ih ) ices depending on the composition of the film. The experiments were conducted with a mixed film of 300 monolayers in thickness and the ACN : H2 O monolayer ratios were varied from 1 : 5 to 5 : 1. Mixed films were deposited at 10 K and warmed to 130–135 K, where ACN desorbed subsequently and IR spectral evolution was monitored continuously. While the emergence of ice Ic at 130 K has been reported, the occurrence of ice Ih at this temperature was seen for the first time. Detailed investigations showed that ice Ih can form at 125 K as well. Crystallization kinetics and activation energy ( E a ) for the emergence of ice Ih were evaluated using the Avrami equation.