Unit Cell Transformations

Experimental features for changing unit cell settings.

Typed commands

STDS MATR r11 r12 r13 tx r21 r22 r23 ty r31 r32 r33 tz transforms the unit cell by rotation matrix r and translation vector t.

STDS TRAN tx ty tz transforms the unit cell by translation vector t, i.e. performs a unit cell origin shift.

STDS INV inverts the current structure.

STDS attempts to transform a unit cell to the standard space group setting, e.g. P21/a or P21/n to P21/c. This can be useful when comparing structures. This does not take account of additional centring operations in all cases. This feature is still under development and has only been implemented for the following space groups:

Triclinic: P1(1), P-1(2). Transform to cell with all axes acute or all obtuse.

Monoclinic: P2(3), P21(4), C2(5), Pm(6), Pc(7), Cm(8), Cc(9), P2/m(10), P21/m(11), C2/m(12), P2/c(13), P21/c(14), C2/c(15). Transforms to cell with beta angle unique, obtuse, and closest value to 90 degrees possible in standard setting.

Orthorhombic: P21212(18), P212121(19), Pca21(29), Pna21(33), Pccn(56), Pbcn(60), Pbca(61), Pnma(62). Note that more than one axis choice may correspond to the standard setting in some cases and an arbitrary choice will be made.