Applied Chemical Engineering

A comparative study of the theoretical and practical values of ionization constants for amino acid derivatives in the neutral and anionic states

Mohammed Abdulrazaq Mahdy

General Directorate of Education in Nineveh, Mosul, 42001, Iraq

Noor H. M. Saeed

Chemistry Department, College of Education for pure sciences, University of Mosul, Mosul, 42001, Iraq

DOI: https://doi.org/10.59429/ace.v8i4.5796

Keywords: density functional theory; ionization constants; theoretically calculation; basisi set; amino acids derivative

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Abstract

A theoretical study was conducted to determine the ionization constants of several amino acid derivatives (2,4-dinitrophenyl amino acids) through density functional theory and using two types of basic bases, CC PV-DZ and (6311-G)d,p. The accuracy of these two bases was determined in the negative and neutral states of the studied compounds. This was achieved by studying several physical variables and theoretically calculated energy functions, and the extent of their correlation with the values of the ionization constants calculated practically, where these variables were linked to the known values of amino acids. The results derived from this correlation were found to be good. The basic rule showed greater accuracy in the theoretical results when compared to the experimental results. There was also greater agreement between the results for the compounds in the negative state, more recently than in the neutral state, due to the electronic interpretations of the chemical structures of the compounds studied in the negative state.

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