First principle periodic calculation was used to determine the feasibility of topotactic exchange and stability of bivalent metal cations inside lithium manganate, which help solid-state chemists to rational design and construction of new-nonmolecular materials. Among the bivalent metal ions strontium-incorporated lithium manganate shows better performance. The location and orientation of the metal cations are also monitored. Projected density of state calculations using periodic boundary conditions justifies the superiority of strontium-incorporated material. The spin and orbital ordering in the material is also explored. The findings further help to propose a novel topotactic valence manipulation scheme for related compounds. (C) 2002 Elsevier Science B.V. All rights reserved.