  We have studied the structural, magnetic properties, and electronic structure
of the compound InCuPO5 synthesized by solid state reaction method. The
structure of InCuPO5 comprises of S = 1/2 uniform spin chains formed by
corner-shared CuO4 units. Magnetic susceptibility chi(T) data shows a broad
maximum at about 65 K, a characteristic feature of one-dimensional (1D)
magnetism. The chi(T) data is fitted to the coupled, S = 1/2 Heisenberg
antiferromagnetic (HAFM) uniform chain model that gives the intra-chain
coupling (J/kB) between nearest neighbour Cu2+ ions as -100 K and the ratio of
inter-chain to intra-chain coupling (J'/J) as about 0.07. The exchange
couplings estimated from the magnetic data analysis are in good agreement with
the computed values from the electronic structure calculations based on density
functional theory + Hubbard U (DFT+U) approach. The combination of theoretical
and experimental analysis confirms that InCuPO5 is a candidate material for
weakly coupled S = 1/2 uniform chains. A detailed theoretical analysis of the
electronic structure further reveals that the system is insulating with a gap
of 2.4 eV and a local moment of 0.70 muB /Cu.
