Spacetimes admitting quasi-conformal curvature tensor

‎The object of the present paper is to study spacetimes admitting‎ ‎quasi-conformal curvature tensor‎. ‎At first we prove that a quasi-conformally flat spacetime is Einstein‎ ‎and hence it is of constant curvature and the energy momentum tensor of such a spacetime satisfying‎ ‎Einstein's field equation with cosmological constant is covariant constant‎. ‎Next‎, ‎we prove that if the perfect fluid pacetime with‎ ‎vanishing quasi-conformal curvature tensor obeys Einstein's field equation without cosmological constant‎, ‎then the spacetime has constant energy density and isotropic pressure and the perfect fluid always behave‎ ‎as a cosmological constant and also such a spacetime is infinitesimally spatially isotropic relative to the unit timelike vector field $U$‎. ‎Moreover‎, ‎it is shown that in a purely electromagnetic distribution the spacetime with vanishing quasi-conformal curvature tensor is filled with‎ ‎radiation and extremely hot gases‎. ‎We also study dust-like fluid spacetime with vanishing quasi-conformal curvature tensor.