Hexagonal Lattice (n,m) nanotubes
a1
a2
x
y
(0,0)
(1,0)
(2,0)
(3,0)
(1,1)
(2,1)
Zigzag
Armchair
(2,2)
(4,0)
(5,0)
(6,0)
(3,1)
(4,1)
(5,1)
(3,2)
(4,2)
(5,2)
(7,0)
(8,0)
(9,0)
(6,1)
(7,1)
(8,1)
(6,2)
(7,2)
(8,2)
(10,0)
(11,0)
(9,1)
(10,1)
(9,2)
(10,2)
(3,3)
(4,3)
(5,3)
(6,3)
(7,3)
(8,3)
(9,3)
(4,4)
(5,4)
(6,4)
(7,4)
(8,4)
(9,4)
(5,5)
(6,5)
(7,5)
(8,5)
(6,6)
(7,6)
(8,6)
(7,7)
n - m = 3q (q: integer):
metallic
n - m ¹ 3q (q: integer): semiconductor