[01] Isa Kazeman, Department of Chemistry, K. N. Toosi University of Technology (KNTU), Tehran, Iran. [02] Sattar Mahmodi, Department of Chemistry, Payam Noor University, Tehran, Iran. [03] Mohammad Hasanzadeh, Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran;Pharmaceutical Analysis Research Center, Tabriz University of Medical Sciences, Tabriz, Iran. [04] Nasrin Shadjou, Department of Nanochemistry, Nano Technology Research Center and Faculty of Chemistry, Urmia University, Urmia, Iran.

Extensive ab inito calculations have been performed in HF, DFT and MP2 levels for several possible structures of methanol clusters (CH3OH)n, n = 1-6. The calculations of the structures, primary and secondary hydrogen bond properties, stabilization energy, vibrational frequencies and intensities of eighteen minima of methanol clusters have been presented perfectly. In this work, a systematic study for 18 possible structures of methanol clusters, from isolated molecule to six molecules in the gas phase. This work reports all of the stable geometry parameters, O-H stretching frequencies in clusters and denotes to distinguished molecules with intensities at any molecules, oxygen and hydrogen charge in clusters and primary and secondary hydrogen bond strength performed with the methods. Cyclic, chain and branched-cyclic are structural types that methanol clusters have been shown in these frameworks.

Ethanol-Water Clusters, Secondary Hydrogen Bond, Electron Density, Hydrogen Bonds

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