. Author manuscript; available in PMC: 2006 Apr 7.

Published in final edited form as: J Phys Chem A. 2000 Jun 29;104(25):6069–6076. doi: 10.1021/jp000038y

TABLE 3.

Relative Energies within a Family of Structures for the Conformers of Protonated Bradykinin Calculated Using Mechanics (MMFF) and DFT (EDF1 6-31G*//EDF1 6-31G*)^a

conformer	d_rms,min (Å)	rel energy (MMFF) (kcal/mol)	EDF1//EDF1 energy (hartrees)	rel energy (EDF1) (kcal/mol)
Salt Bridge (IV)
1	1.2	0.0	−3599.063 036	5.6
2	0.9	1.2	−3599.066 052	3.7
3	0.8	4.0	−3599.057 249	9.3
4	0.8	4.7	−3599.072 021	0.0
5	1.7	5.0	−3599.070 107	1.2
6	2.3	5.7	−3599.055 085	10.6
7	0.9	9.3	−3599.058 632	8.4
N-Terminal (V)
1	2.1	0.0	−3599.038 599	2.3 (21.0)
2	2.1	6.6	−3599.035 441	4.3 (23.0)
3	3.1	5.7	−3599.042 316	0.0 (18.7)
C-Terminal (VI)
1	2.2	0.0	−3599.042 027	5.9 (18.8)
2	2.2	3.5	−3599.051 392	0.0 (12.9)
3	3.5	12.1	−3599.039 154	7.7 (20.6)

The values in parentheses are the DFT energies of the conformer relative to the most stable conformer (IV4). The number of conformers which contain two β turns (from Arg¹ to Gly⁴ and from Ser⁶ to Arg⁹) are in bold typeface.