sknano.structures.SWNT.t2

SWNT.t2

$t_2 = -\frac{2n + m}{d_R}$

where $d_R = \gcd{(2n + m, 2m + n)}$.

The component of the translation vector $\mathbf{T}$ along $\mathbf{a}_2$:

$$\mathbf{T} = t_1\mathbf{a}_1 + t_2\mathbf{a}_2$$