topochemical reaction

Synonym: topotactic reaction
A reversible or irreversible reaction that involves the introduction of a guest species into a host structure and that results in significant structural modifications to the host, for example, the breakage of bonds. Example: The insertion of lithium at 50°C into the spinel Li[Mn2]O4 with symmetry F d3m to yield a layered structure with symmetry P 3 ̄ m1.
Alternative terms: topotactic reaction, insertion reaction.
PAC, 1994, 66, 577. 'Definitions of terms relating to phase transitions of the solid state (IUPAC Recommendations 1994)' on page 592 (