Syntax

NCS STRIct

{ <NCS-strict-statement> } END is invoked from the main level of X-PLOR.

<NCS-strict-statement>:==

INITialize

erases the strict NCS database.

NCSRelations

<matrix> [TRANslation=<vector>] specifies relationships in addition to XNCSrelations, between the input coordinates and their equivalents, to specify completely the internal symmetry for nonbonded interactions. These must be given only after all XNCSrelations have been given. The matrix gives the matrix , the vector the translation vector .

SKEW

<matrix> [TRANslation=<vector>] specifies the relationship between the crystal and skew frames. The matrix specifies the matrix , the vector the translation vector (for the syntax of matrix, see Section 2.4). (default: identity for the matrix and no translation, i.e., no skewing).

XNCSrelations

<matrix> [TRANslation=<vector>] specifies the relationships between the input coordinates and their NCS equivalents. The matrix gives the the matrix , the vector the translation vector . (For the syntax of matrix, see Section 2.4.) The XNCSrelations are used to generate the crystallographic asymmetric unit from the protomer. The identity operation is optional.