Table 1.

x‐H Distances Used in Reduce (Å)

x‐H atoms	e‐cloud	nuclear	example
tetra CH1	0.97	1.09	Val Hb
tetra CH2	0.97	1.09	Glu Hb2,3
tetra CH3	0.97	1.09	Ala Hb1,2,3
planar CH	0.93	1.08	Phe Hd1
tetra NH3	0.89	1.04	Lys Hz1,2,3
planar NH	0.86	1.02	peptide H
tetra OH	0.84	0.98	Ser Hg
tetra SH	1.20	1.30	Cys Hg

Nuclear x‐H distances are from parent atom to H nucleus; “e‐cloud” x‐H distances are from parent atom to the H electron‐cloud center.