Theoretical Considerations on Electronic Properties of Cations of melamine and Methylolmelamine, and a Relationship between the Band Maximum Wavelength of Ultraviolet Absorption Spectrum of Cation of Methylolmelamine and the Number of Methylol Group by the Molecular Orbital Method. (2) Cations of Methylolmelamine

Abstract

The total energies of the cation models of mono-, di-, tri, and tetramethylolmelamines (1 MM, 2 MM, 3 MM, and 4 MM) were calculated to determine the most stable model for each homologue by the CNDO/2 and extended HMO methods.
On the other hand, the transition energies, wavelengths, and oscillator strengths of the most stable cation models of 1 MM, 2 MM, 3 MM, and 4 MM were calculated to obtain the simulation diagrams of their UV spectra by the CNDO/CI method. The maximum wavelength of the absorption curve synthesized from these calculated spectroscopic data changes linearly against the number of methylol group. The above calculated result is in good agreement with the observed behavior of the maximum wavelength of the absorption bands of MM in HCl aqueous solution against the number of methylol group.