Data Item _space_group.transform_Pp_abc

General

Item name
_space_group.transform_Pp_abc
Category name
space_group
Attribute name
transform_Pp_abc
Required in PDB entries
no
Used in currrent PDB entries
No

Item Description

This item specifies the transformation (P,p) of the basis vectors from the setting used in the CIF (a,b,c) to the reference setting given in _space_group.reference_setting (a',b',c'). The value is given in Jones-Faithful notation corresponding to the rotational matrix P combined with the origin shift vector p in the expression: (a',b',c') = (a,b,c)P + p P is a post-multiplication matrix of a row (a,b,c) of column vectors. It is related to the inverse transformation (Q,q) by: P = Q-1 p = Pq = -(Q-1)q These transformations are applied as follows: atomic coordinates (x',y',z') = Q(x,y,z) + q Miller indices (h',k',l') = (h,k,l)P symmetry operations W' = (Q,q)W(P,p) basis vectors (a',b',c') = (a,b,c)P + p This item is given as a character string involving the characters a, b and c with commas separating the expressions for the a', b' and c' vectors. The numeric values may be given as integers, fractions or real numbers. Multiplication is implicit, division must be explicit. White space within the string is optional.
 -b+c, a+c, -a+b+c
 a-1/4, b-1/4, c-1/4
 b-1/2, c-1/2, a-1/2

Data Type

Data type code
char
Data type detail
char item types / multi-word items ...
Primitive data type code
char
Regular expression
[][ \t_(),.;:"&<>/\{}'`~!@#$%?+=*A-Za-z0-9|^-]*