Figure 3
Potential energy well of the #1 B2u optical mode (active in infrared) as obtained from (a) the B3LYP-D3 and (b) the B3LYP-D* approaches. The blue line corresponds to the harmonic approximation (see text for details), whereas the red line is the result of the scan performed along the displacement coordinate of the normal mode. The black thick horizontal line marks the fundamental vibrational energy level, calculated from the harmonic approximation (blue line). (c) Graphical representation of the eigenvectors (yellow arrows) of the #1 B2u optical mode, with calcium, carbon and oxygen atoms in the unit cell coloured in blue, ochre and red, respectively.
