what is crystal field splitting energy

Crystal field splitting energy is the energy difference between the two levels of d-orbitals (eg and t2g) that occurs when the d-orbitals split into two levels in the presence of ligands. This splitting is known as crystal field splitting, and the energy difference between the two levels is called the crystal field splitting energy (Δ0) . The crystal field splitting energy is the parameter used to correlate various spectroscopic, thermodynamic, and magnetic properties of complexes. The crystal field splitting energy is different for different geometries of complexes. For example, for octahedral complexes, the crystal field splitting energy is denoted by Δoct, while for tetrahedral complexes, it is denoted by Δtet. The crystal field splitting energy for tetrahedral complexes is roughly equal to 4/9Δoct (for the same metal and same ligands) .