# Examples of Common Lattices and Symmetries 1007

The following list shows frequently occurring surface lattices and associated highest possible symmetries. Lower symmetries can occur as well, e.g. with low-symmetry adsorption sites, low-symmetry adsorbates, and low-symmetry reconstructions. In (nxm) n and m are assumed unequal; in (nx1) n>1; n and m are always integers.

fcc(111), bcc(111), Si(111), NaCl(111), zincblende(111), hcp(0001), C(0001), wurtzite (0001):
(1x1)                               p3m1
(nxn)                               p3m1
(r3xr3)R30                       p31m
c(4x2)                             pm
(2x1)                               pm
(3x1)                               p2
(r7xr7)R19.1                    p3

fcc(100), bcc(100), NaCl(100):
(1x1)                               p4m
(nxn)                               p4m
c(2x2)                             p4m
c(4x2)                             cmm
(nxm)                              pmm
(2r2xr2)R45                     pmm
(r5xr5)R27                       p4

Si(100), zincblende(100):
(1x1)                               pmm
(2x1)                               pmm [actual Si(100) reconstruction has pm symmetry

fcc(110), hcp(10-10):
(1x1)                               pmm
(nxn)                               pmm
(nxm)                              pmm
c(2x2)                             cmm

bcc(110):
(1x1)                               cmm
(nxn)                               cmm
(nxm)                              p2

Si(110):
(1x1)                               pmg

zincblende(110):
(1x1)                               pm

hcp(10-10):
(1x1)                               pmg

fcc(210), fcc (311), fcc(331), bcc(310):
(1x1)                               cm

bcc(210), bcc(211):
(1x1)                               pm