<b>A COMPUTATIONAL STUDY ON THE HYDROGEN-BONDED COMPLEXES FORMED BY THE ANTHYRIDONE AND DIALDEHYDE DERIVATIVES</b>

Abstract

A theoretical study on hydrogen-bonded complex 1 formed by anthyridone (monomer A) and 2,6-diaminopyridine-3,5-dialdehyde (monomer B) was performed using the AM1 method to obtain its binding energy. A series of complexes 2 to 9 were designed by changing the R-groups on monomer A in complex 1 into C 6 H 5 , p-toluene, p-phenol, OH, OCH 3 , and turning the X-groups on monomer B into F, Cl, I, respectively. Based on the optimized geometries, the electronic spectra for the complexes were calculated with the INDO/CIS method and the IR spectra were computed utilizing the AM1 method. It was indicated that the dimer could be formed by the two monomers via triple hydrogen bonds because of its negative binding energy. The binding energies of the complexes were changed with the change of the electronic properties and steric effects of the substituents on the monomers. The first absorptions in the electronic spectra of the complexes were red-shifted compared with those of the monomers. The stretching vibrations of the N-H bonds on the monomers were weakened and their frequencies were reduced with the formation of the hydrogen bonds.

<b>THEORETICAL STUDY ON ELECTRONIC STRUCTURES AND SPECTROSCOPY OF TRIARYLBORANE SUBSTITUTED BY THIOPHENE</b>

“…Compounds 12 and 13 are formed by replacing the aryl rings in BPh 3 using two and three thiophene rings. The AM1 [12] and B3LYP methods [13,14] are successfully used to study the electronic structures and IR frequencies of the supra-molecular aggregates [15][16][17][18], the 13 C chemical shifts of the amino acids [19], the catalytic reactions [20], and the properties of the other organic compounds [21]. In view of computation time and accuracy, the AM1 method is first used, followed by B3LYP method with 6-31G(d) basis set in density function theory (DFT).…”

<b>THEORETICAL RESEARCH ON EFFECTS OF SUBSTITUENTS AND THE SOLVENT ON QUADRUPLE HYDROGEN BONDED COMPLEXES</b>

“…The binding energy ∆E of a complex is equal to the total energy of the complex minus the energies of the two monomers [7,[10][11][12][13]. Oligophenyleneethynylene (monomer A), isophthalic acid (monomer B) and complex 1 formed by them are optimized using the AM1 method [14].…”