Non-intrusive spectroscopic probing of weakly bound van der Waals complexes forming in gaseous carbon dioxide is generally performed at low pressures, for instance in supersonic jets, where the low temperature favors dimers, or in few-atmosphere samples, where the signature of dimers varying as the squared gas density is entangled with the dominating collision-induced absorption. We report experimental and theoretical results on CO2 dimers at very high pressures approaching the liquid phase. We observe that the shape of the CO2 -dimer bands undergoes a distinctive line-mixing transformation, which reveals an unexpected stability of the dimers despite the collisions with the surrounding particles and negates the common belief that CO2 dimers are short-lived complexes. Our results furnish a deeper insight allowing a better modeling of CO2 -rich atmospheres and provide also a new spectroscopic tool for studying the robustness of molecular clusters.
The purpose of The Journal of Chemical Physics is to bridge a gap between journals of physics and journals of chemistry by publishing quantitative research based on physical principles and techniques, as applied to "chemical" systems. Just as the fields of chemistry and physics have expanded, so have chemical physics subject areas, which include polymers, materials, surfaces/interfaces, and biological macromolecules, along with the traditional small molecule and condensed phase systems. The Journal of Chemical Physics (JCP) is published four times per month (48 issues per year) by the American Institute of Physics.
The American Institute of Physics (AIP) is a 501(c)(3) not-for-profit membership corporation created for the purpose of promoting the advancement and diffusion of the knowledge of physics and its application to human welfare. It is the mission of the Institute to serve the sciences of physics and astronomy by serving its member societies, by serving individual scientists, and by serving students and the general public.
As a "society of societies," AIP supports ten Member Societies and provides a spectrum of services and programs devoted to advancing the science and profession of physics. A pioneer in digital publishing, AIP is also one of the world's largest publishers of physics journals and produces the publications of more than 25 scientific and engineering societies through its New York-based publishing division.
