. Author manuscript; available in PMC: 2017 Feb 22.

Published in final edited form as: J Phys Chem B. 2015 Dec 22;120(1):69–76. doi: 10.1021/acs.jpcb.5b09881

Table 2.

Components of the Enthalpy Change in the Coil-to-Helix Transition for the Coil States Noted Below^a

coil	ΔE_reorg	ΔE_bb–w	ΔE_sc–w	ΔE_int	Δh_total
C₀	−17.0(8.0)	34.0(0.4)	1.9(0.2)	−43.3	−24.0(8.0)
C₇	−23.0(6.0)	51.1(0.2)	−0.6(0.2)	−55.0	−28.0(6.0)

The change in excess enthalpy (Δh^ex) reveals the role of hydration and the change in internal energy (ΔE_int) the role of intramolecular interactions. Δh^ex is further divided into ΔE_reorg, the change in the water reorganization contribution, and ΔE_sw, the peptide–water interaction contribution. The latter is subdivided into contributions from the backbone water, ΔE_bb–w, and side chain water, ΔE_sc–w, interactions. Standard error of the mean is given in parentheses at the 2σ level. All values are in kcal/mol.