Decomplexation or Fragmentation
Decomplexation or fragmentation is the reverse of complexation. However, where complexation is a bimolecular (second order) process, decomplexation is a unimolecular (first order) process.

Fragmentation into a Lewis acid/base pair is termed "heterolysis" and fragmentation into a pair of radicals is termed "homolysis".

For more information look in the Chemogenesis webbook sections on fragmentation reactions.