Super-molecule

Method/Basis_set/Scaling factor

Imaginary Frequency (cm⁻¹)^*

n

Minimal

Maximal

B3LYP/6-311+G^**/1.05²

1

−5.07

−5.07

Ge(OH)₄-(H₂O)₃₀

B3LYP/6-311+G^**/1.05²

1

−22.23

−22.23

Calcite cluster

HF/3-21G/0.91

76

−7119.47

−11.93

Calcite cluster

B3LYP/6-31G/0.97

151

−3321.80

−69.95