Wavelength and Colour in Coordination complexes My textbook said that coordination complexes with weak field ligands require a larger wavelength for obtaining enough energy for electron transfer(and hence, the manifestation of a colour), but if E = hv(E is the energy, h is Planck's Constant and v is the frequency), then shouldn't the wave of higher frequency be needed?
Low spin (formed from strong field ligands) complexes result in a larger difference in energy between the $t_{2}g$ and $e_{g}$ orbitals. High spin (caused by weak field ligands) complexes are, evidently, the opposite.
This means thats high spin complexes require lower energy photons than low spin. Since wavelength and frequency are inversely proportional, high spin complexes require lower frequency (longer wavelength) photons to promote transitions.