A DISCOVERY WAS MADE OF AN ELECTRICALLY INDUCED IMPURITY PHOTOCONDUCTIVITY OF INDIUM SELENIDE SINGLE CRYSTALS. A STUDY OF THIS EFFECT IN COMPARISON WITH AN ELECTRIC-FIELD-STIMULATED NEGATIVE PHOTOCONDUCTIVITY AND WITH INFRARED QUENCHING OFTHE RESIDUAL CONDUCTIVITY OF THE SAME SAMPLE REVEALED THAT ALL THREE EFFECTS WERE INDUCED BY INJECTION. HOWEVER, THE ELECTRICALLY INDUCED IMPURITY PHOTOCONDUCTIVITY WAS DUE TO THELIBERATION OF THE MAJORITY CARRIERS FROM TRAPS, WHEREAS THEOTHER TWO EFFECTS WERE ASSOCIATED WITH SLOW (R) CENTERS WHERE RECOMBINATION OF THE MINORITY CARRIERS TOOK PLACE. THE DEPTH OF THE R CENTERS WAS CONSIDERABLY GREATER THAN THE DEPTHOF THE TRAPS, AND THESE IMPURITY LEVELS WERE SPATIALLY SEPARATED, SO THAT ALL THESE EFFECTS COULD BE STUDIED INDEPENDENTLY IN THE SAME SAMPLE.