Cross section for photoelectron capture by IrBr3−6 in AgBr

The lifetime of photogenerated electrons in AgBr crystals doped with trivalent iridium ions was determined from photoconductivity measurements. A first-order electron decay process occurs at Ir3+ sites, with a room-temperature photoelectron lifetime of 13–150 ps for materials with 89–4 ppm of dopant. A cross section of 26±5 Å2 was deduced for photoelectron capture by IrBr3−6 centers.