Table 5.

HOMO ($E_{\mathrm{LCAO},\mathrm{H}}$) and LUMO ($E_{\mathrm{LCAO},\mathrm{L}}$) eigenenergies of the base pairs A-T and G-C, obtained in this work using LCAO with all valence orbitals, along with the corresponding HOMO–LUMO energy gaps ($E_{\mathrm{LCAO},\mathrm{g}}$) in eV (rows 6 and 7). Rows 2–5 contain the calculated HOMO and LUMO energies of each distorted base making up these base pairs. The third, fifth, and the seventh columns list the corresponding energies from Reference [52] where only 2p${}_z$ orbitals had been used.

Base or Base Pair	${\mathit{E}}_{\mathbf{LCAO},\mathit{H}}$	${\mathit{E}}_{\mathit{H}}$ [52]	${\mathit{E}}_{\mathbf{LCAO},\mathit{L}}$	${\mathit{E}}_{\mathit{L}}$ [52]	${\mathit{E}}_{\mathbf{LCAO},\mathit{g}}$	${\mathit{E}}_{\mathit{g}}$ [52]
A	$-8.50$	$-8.30$	$-4.19$	$-4.40$	$4.31$	$3.90$
T	$-9.12$	$-9.00$	$-4.30$	$-4.90$	$4.82$	$4.10$
G	$-8.31$	$-8.00$	$-4.12$	$-4.50$	$4.19$	$3.50$
			$-4.43$ (${\sigma }^{*}$)		$4.24$ ($\pi \to {\sigma }^{*}$)
C	$-8.67$	$-8.80$	$-4.11$	$-4.30$	$4.56$	$4.50$
A-T	$-8.49$	$-8.30$	$-4.31$	$-4.90$	$4.18$	$3.40$
			$-4.43$ (${\sigma }^{*}$)		$3.87$ ($\pi \to {\sigma }^{*}$)
G-C	$-8.30$	$-8.00$	$-4.14$	$-4.50$	$4.16$	$3.50$