Simulated properties of Aβ 40 sampled with different force fields.

Quantity	Force fields
	a03ws	a99SB-ILDN/TIP4P-D	a99SB-UCB	a99SB-disp	a99SB*-ILDN/TIP3P	C22*/TIP3P	C36m
RMSDexp Cα-shift (ppm)	0.738	0.589	0.641	0.631	0.759	0.688	0.634
RMSDRC Cα-shift (ppm)a	0.678	0.555	0.593	0.580	0.706	0.627	0.572
RMSDexp C′-shift (ppm)	1.025	0.964	0.927	0.929	0.984	0.961	0.978
RMSDRC C′-shift (ppm)a	1.211	1.077	1.041	1.117	1.209	1.188	1.177
χ 2 J-coupling	7.03	3.28	1.94	4.50	6.33	2.50	3.05
〈Ree〉 ± S.D. (nm)b	2.64 ± 1.60	3.97 ± 1.53	4.22 ± 1.68	3.17 ± 1.25	2.22 ± 0.82	2.67 ± 1.14	3.09 ± 1.54
〈EFRET〉 ± S.D.	0.83 ± 0.26	0.65 ± 0.31	0.59 ± 0.33	0.81 ± 0.23	0.96 ± 0.06	0.88 ± 0.17	0.80 ± 0.27
〈Rgyr〉 ± S.D. (nm)	1.31 ± 0.30	1.65 ± 0.30	1.76 ± 0.40	1.38 ± 0.30	1.11 ± 0.08	1.24 ± 0.20	1.45 ± 0.30
〈Rhyd〉 ± S.D. (nm)	1.62 ± 0.16	1.77 ± 0.13	1.80 ± 0.13	1.66 ± 0.11	1.53 ± 0.05	1.60 ± 0.11	1.69 ± 0.13

^aFor the calculation of the RMSD with respect to the RC chemical shifts, the RC values and correction factors determined in ref. 65 and 66 for IDPs at 300 K and pH 7 were used.

^bS.D. = standard deviation.