Table 5. Review of Molecular Descriptors for Glycine in Water^a.

details	Ion. energy	El. affinity	Electroneg.	Hardness	Dip. mom.	Polarizabil.	Reduct. pot.
Amino Acid Form
ΔSCF (v) BS1	134	21	56	77	1.826	43.4
+MP2 corr. (v) BS1	167	13	77	90	1.721	47.1
MP2 (a) BS1	149	–19.7	84	64	1.736	48.4	0.97
MP2 (a) BS2	151	–25.0	88	63	1.780	55.4	1.02
DFT (a) BS2	147	–25.1	86	61	1.754	56.8	1.21
Zwitterionic Form
MP2 (a) BS1	150	–16.5	83	67	13.51	49.7	0.85
MP2 (a) BS2	163	–14.1	88	74	14.53	58.1	0.86
DFT (a) BS2	150	–18.9	84	66	13.88	58.8	1.05

^aBasis sets BS1 = def2-TZVP, BS2 = def2-TZVPD; units as in Table 2; (v), vertical ionization process; (a), adiabatic process.