Bilbao Crystallographic Server Plain text output Generators and general positions

Generators/General Positions

To obtain the information about the generators or the general positions of a group in text form you have to give the command
GET /cgi-bin/cryst/text/nph-list_gen?g=[gn]&ua=[ua]&or=[or]&rh=[rha]&w=[w]
where

• [gn] is the group number in ITA,
• ua, or, rh are used to specify the unique axis ([ua]), the origin choice ([oc]) or the hexagonal or rhombohedral axes ([rha]) for the groups for which there is more than one possibility. The possible values are: [ua] = b|c, [oc]= o|t where o corresponds to origin choice one and t -- to origin choice two, [rh]=h|r. If no value is specified the default choice will be used.
• If you do not specify if you want to see the generators or the general positions you will obtain the general positions. To take the generators you have to give [w]=gen.

For example if you want to obtain the generators of the group 012( C 2/m) [unique axis b] you have to do the following:

telnet www.cryst.ehu.es 80
GET /cgi-bin/cryst/text/nph-list_gen?g=12&ua=b&w=gen 

The output you will obtain has the following form:

headers ..

# Bilbao Crystallographic Server (www.cryst.ehu.es)
# Generators of the group 012( C 2/m) [unique axis b]
x,y,z
[  1.000000  0.000000  0.000000  0.000000 ]
[  0.000000  1.000000  0.000000  0.000000 ]
[  0.000000  0.000000  1.000000  0.000000 ]
[  0.000000  0.000000  0.000000  0.000000 ]

-x,y,-z
[ -1.000000  0.000000  0.000000  0.000000 ]
[  0.000000  1.000000  0.000000  0.000000 ]
[  0.000000  0.000000 -1.000000  0.000000 ]
[  0.000000  0.000000  0.000000  0.000000 ]

-x,-y,-z
[ -1.000000  0.000000  0.000000  0.000000 ]
[  0.000000 -1.000000  0.000000  0.000000 ]
[  0.000000  0.000000 -1.000000  0.000000 ]
[  0.000000  0.000000  0.000000  0.000000 ]

x+1/2,y+1/2,z
[  1.000000  0.000000  0.000000  0.500000 ]
[  0.000000  1.000000  0.000000  0.500000 ]
[  0.000000  0.000000  1.000000  0.000000 ]
[  0.000000  0.000000  0.000000  0.000000 ]

# end of the list