Core dictionary (coreCIF) version 2.4.5
The measure of absolute structure as defined by Rogers (1981). The value must lie in the 99.97% Gaussian confidence interval -1 -3u =< \h =< 1 + 3u and a standard uncertainty (e.s.d.) u must be supplied. The _enumeration_range of -1.0:1.0 is correctly interpreted as meaning (-1.0 - 3u) =< \h =< (1.0 + 3u). Ref: Rogers, D. (1981). Acta Cryst. A37, 734-741.
The permitted range is -1.0 -> 1.0