  First principles calculations are performed to investigate the
thermodynamical stability, dynamical, mechanical, electronic and magnetic
properties of CrTiCoZ (Z= Al/Si) novel quaternary Heusler alloys. Y-type III
atomic configuration is found to be the most stable structure for both
compounds. The melting temperatures of both compounds are as high as 2142 K and
2420 K for CrTiCoAl and CrTiCoSi, respectively. The electronic structure
calculations using GGA-PBE approach show a half metallic behavior of CrTiCoAl.
The spin-down channel exhibits a direct band gap of 0.15 eV, whereas the
spin-up channel is metallic making CrTiCoAl a half metallic ferromagnet with
100% spin polarization and an appreciable magnetic moment of -2 Bohr Magnetons.
The Curie temperature of CrTiCoAl is well above the room temperature (385K),
whereas that of CrTiCoSi is below the room temperature (203K).
