  The half metallic properties of Ti\raisebox{-.2ex}{\scriptsize 2}CoSn
full-Heusler compound is studied within the framework of the density functional
theory with the Perdew Burke Ernzerhof generalized gradient approximation
(GGA). Structural optimization was performed and the calculated equilibrium
lattice constant is 6.340 A. The spin up band of compound has metallic
character and spin down band is semiconducting with an indirect gap of 0.598 eV
at equilibrium lattice constant. For the lattice parameter, ranging from 6.193
to 6.884 A the compound presents 100% spin polarization and a total magnetic
moment of 3$\mu_{B}$.
