Quantum-Chemical Prediction of Molecular and Electronic Structure of Carbon-Nitrogen Chemical Compound with Unusual Ratio Atoms: C(N20)

Abstract

Using various versions of quantum-chemical calculation, namely four versions of density functional theory (DFT), (DFT B3PW91/TZVP, DFT M06/TZVP, DFT B3PW91/Def2TZVP, and DFT M06/Def2TZVP) and two versions of the MP method (MP2/TZVP and MP3/TZVP), the existence possibility of the carbon-nitrogen-containing compound having an unusual M: nitrogen ratio of 1:20, unknown for these elements at present, was shown. Structural parameters data are presented; it was noted that, as may be expected, CN₄ grouping has practically a tetrahedral structure, and the chemical bond lengths formed by nitrogen atoms and a carbon atom in the frameworks of each of the calculation methods indicated above are equal to each other. Thermodynamical parameters, NBO analysis data, and HOMO/LUMO images for this compound are also presented. A good agreement between the calculated data obtained using the above three quantum-chemical methods was noticed, too.

Keywords: C(N20); carbon-nitrogen compound; molecular structure; quantum-chemical calculation method.

Figure 1

Molecular structure of the C(N₂₀) compound obtained as a result of MP3/TZVP quantum-chemical calculation.

Figure 2

The images of highest occupied (HOMO) and lowest unoccupied (LUMO) molecular orbitals in the C(N₂₀) (ground state—spin singlet, M_S = 1) according to DFT B3PW91/TZVP, DFT B3PW91/Def2TZVP, DFT M06/TZVP, and DFT M06/Def2TZVP methods. The energies values of these molecular orbitals (in brackets) are given in eV.