Critical points in the Brioullin zone
 
Symbol    Description
Γ      Center of the Brillouin zone
 
Simple cube
M      Center of an edge
R      Corner point
X      Center of a face
 
Face-centered cubic
K      Middle of an edge joining two hexagonal faces
L      Center of a hexagonal face
U      Middle of an edge joining a hexagonal and a square face
W      Corner point
X      Center of a square face
 
Body-centered cubic
H      Corner point joining four edges
N      Center of a face
P      Corner point joining three edges
 
Hexagonal
A      Center of a hexagonal face
H      Corner point
K      Middle of an edge joining two rectangular faces
L      Middle of an edge joining a hexagonal and a rectangular face
M      Center of a rectangular face
 
Spacegroup = 2 (triclinic ; P-1)
 
Symbol    kx,ky,kz
Z      0, 0, 1/2
Y      0, 1/2, 0      
X      1/2, 0, 0      
V      1/2, 1/2, 0      
U      1/2, 0, 1/2      
T      0, 1/2, 1/2      
R      1/2, 1/2, 1/2      
M      1/2, 1/2, 1/2  (?)
C      0 , 1/2, 1/2 (?)
 
See also:
Brillouin zone
http://www.oraxcel.com/cgi-bin/yabb2/YaBB.pl?num=1250678083/0#0
 
Source:
Brillouin Zone - Wikipedia
http://en.wikipedia.org/wiki/Brillouin_zone#Critical_points
bilbao crystallographic server
k-vector types and Brillouin zones of the space groups
http://www.cryst.ehu.es/cryst/get_kvec.html