Table 2.

Energy properties of the radical anions, the transition states, and the C_5′O_5′ σ bond-broken complexes of the pyrimidine nucleotides

Species	E, hartree	ΔE, kcal/mol	ΔE0, kcal/mol	ΔG0, kcal/mol
5′-dCMPH−	−1423.22913	0.00	0.00	0.00
TS5′-dCMPH−	−1423.20638	14.27 (17.97)†	12.52	12.75
		0.62 (0.78)†	0.54	0.55
Cytidine-C5′ (HH′)-yl	−1423.26574	−22.97 (−19.19)†	−24.40	−25.97
+ MeOPO3H−		−1.00 (−0.83)†	−1.06	−1.13
5′-dTMPH−	−1482.45023	0.00	0.00	0.00
TS5′-dTMPH−	−1482.42817	13.84 (17.86)†	11.91	11.82
		0.60 (0.77)†	0.52	0.51
Thymidine-C5′ (HH′)-yl	−1482.48372	−21.01 (−16.05)†	−22.77	−23.19
+ MeOPO3H−		−0.91 (−0.70)†	−0.99	−1.00

ΔE⁰, zero point energy corrected. ΔG⁰, free energy difference at 298 K. The unit of the numbers in bold is eV.

^†Polarizable continuum model (PCM), based on the gas-phase optimized structure and using water as solvent with ε = 78.39.