Processes of the development of the molecular world at early stages of its formation: Evidence from the investigation of the behavior of the vibrational entropy of molecules

• Published in: Geochemistry international 2016-11, Vol.54 (11), p.929-935
• Main Authors: Baranov, V. I., Gribov, L. A., Mikhailov, I. V.
• Format: Article
• Language: English
• Subjects: Atomic structure; Biosphere; Carbon-carbon composites; Earth and Environmental Science; Earth Sciences; Elasticity; Entropy; Evolution; Geochemistry; Hydrogen bonds; Molecular structure; Molecules
• ISSN: 0016-7029; 1556-1968
• DOI: 10.1134/S0016702916110021

We analyzed the possibility of explaining empirical relations in the evolution of the molecular world on the basis of fundamental physical laws and theories of the behavior of the entropy of a system. Quantitative expressions were evaluated describing the entropy of internal motion of atoms in a molecular ensemble (vibrational entropy), which is a term of total entropy with a clear physical meaning. It was shown that vibrational entropy is controlled primarily by the structure of the compound rather than the number and identity of atoms in the molecule. During the early stages of evolution, the appearance of acyclic structures is more advantageous than that of cyclic structures. An increase in the complexity of the molecular world inevitably leads to the appearance of molecules with a complex skeleton formed mainly by bonds of the same elasticity as C–C. The necessity of helical structures, whose spatial elasticity is provided by hydrogen bonds, was explained.