  The band structure, optical and defects properties of Ba_{2}TeO are
systematically investigated using density functional theory with a view to
understanding its potential as an optoelectronic or trans- parent conducting
material. Ba_{2}TeO crystallizes with tetragonal structure (space group P4/nmm)
and with a 2.93 eV optical band gap 1 . We find relatively modest band masses
for both electrons and holes suggesting applications. Optical properties show a
infrared-red absorption when doped. This could potentially be useful for
combining wavelength filtering and transparent conducting functions.
Furthermore, our defect calculations show that Ba_{2}TeO is intrinsically
p-type conducting under Ba-poor condition. However, the spontaneous formation
of the donor defects may constrain the p-type transport properties and would
need to be addressed to enable applications.
