A1 = C₄₄/(C₁₁ + C₃₃ − 2C₁₃)

A2 = 4C₅₅/(C₂₂ + C₃₃ − 2C₂₃)

A3 = 4C₆₆/(C₁₁ + C₂₂ − 2C₁₂)

Graphene

−0.00087

−0.00087

1

Silicene

0.0024

0.002398

0.999999

Germanene

−0.1669

−0.1669

1.000001

Stenane

−0.01893

−0.01893

1.000002