We report an enhancement of the superconducting transition temperature (Tc) when chromium (Cr) is substituted in excess at the iron (Fe) site (FeCr _xSe, x=0.01, 0.02 and 0.03). There is a corresponding increase in the superconducting volume fraction with Tc attaining a value of 11.2 K on 2 Cr substitution when compared to a Tc of 8.5 K for the conventional tetragonal Fe-excess sample Fe_(1+x)Se. The results point to the role of chemical pressure (introduced via ionic size variation at the Fe site upon Cr substitution in excess) on superconducting properties.
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