Table 4.

Differences in entropy, TΔS^A (kcal/mol) between the extended, helical and hairpin microstates of (Gly)₁₀ obtained by HSMD^a

	Unit=1500 n=400			Unit=500 n=400		Unit=2000 n=200	Flexible model
	nf = 24000	nf = 6000	nf = 2000	nf = 1000	nf = 500	nf = 6000
T(Sextend - Shairpin)	2.9 (1)	2.9 (2)	2.9 (2)	2.9 (2)	2.9 (2)	2.8 (3)	3.0 (3)
T(Sextend - Shelix)	4.0 (1)	4.0 (1)	4.0 (1)	4.0 (1)	4.0 (1)	3.9 (2)	4.0 (3)
T(Shairpin -Shelix)	1.1 (1)	1.2 (1)	1.2 (1)	1.1 (1)	1.1 (1)	1.2 (1)	1.0 (2)

^aThe simulations were carried out in vacuum at a low temperature, T=100 K - to keep the system in the three microstates (Cheluvaraja and Meirovitch, 2006). n is the size of the reconstructed MD sample; n_f is the sample size of the future chains, n_f =jn’_f where n’_f is the unit size. The statistical error is defined in Table 1. The table shows that the results for TΔS^A are very stable i.e., they are equal (within the error bars) for a range of n_f values between 24000 and 500. The results for n_f=24000 are considered to be the correct results for TΔS. The HSMD results are very close to those obtained by Cheluvaraja and Meirovitch, 2004 using HSMC for the “flexible model” of (Gly)₁₀ where the bond lengths are constant but the bond angles are allowed to change.