Lithuanian Journal of Physics article / Lietuvos fizikos žurnalo straipsnis

CONFORMATIONAL ANALYSIS OF SMALL ETHANOL CLUSTERS TRAPPED IN A LOW-TEMPERATURE ARGON MATRIX
Iryna Doroshenko^a,b, Askar Nekboev^c, and Bahrom Kuyliev^c
^aTaras Shevchenko National University of Kyiv, 64/13 Volodymyrska Street, 01601, Kyiv, Ukraine
^bUniversity of Gothenburg, Universitetsplatsen 1, 405 30, Gothenburg, Sweden
^cKarshi State University, 17 Kuchabog Street, 180119, Karshi, Uzbekistan
Email: dori11@knu.ua

Received 29 October 2025; accepted 19 November 2025

This work presents a conformational analysis of ethanol molecules and their clusters isolated in a low-temperature argon matrix using FTIR spectroscopy and quantum-chemical calculations. Optimal geometry, energy parameters and vibrational frequencies for trans and gauche conformations of ethanol, as well as for various possible combinations of conformers in dimers, trimers and tetramers, were calculated. Temperature-dependent FTIR spectra reveal distinct bands corresponding to the O–H stretching vibrations of both conformers. As the matrix temperature increases from 20 to 50 K, ethanol monomers progressively form hydrogen-bonded clusters. Quantum-chemical modelling confirms the presence of all theoretically predicted cluster configurations in the matrix at temperatures about 40 K.
Keywords: ethanol, conformers, argon matrix, FTIR spectroscopy, hydrogen bonding

MAŽŲ ETANOLIO KLASTERIŲ ŽEMOS TEMPERATŪROS ARGONO MATRICOJE KONFORMACINĖ ANALIZĖ
Iryna Doroshenko^a,b, Askar Nekboev^c, Bahrom Kuyliev^c

^aKyjivo nacionalinis Taraso Ševčenkos universitetas, Kyjivas, Ukraina
^bGeteborgo universitetas, Geteborgas, Švedija
^cValstybinis Karšio universitetas, Karšis, Uzbekistanas

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