NOVELTY - A compound containing deuterium (I), is new.    USE - New compound containing deuterium used in organic electric device e.g. organic electroluminescent device, organic solar cell, organic photoreceptor and organic thin film transistor (all claimed).    ADVANTAGE - The deuterated compound provides organic electric device with low drive voltage and improved lifetime.    DETAILED DESCRIPTION - A compound containing deuterium of formula (I), is new.    Ar1-Ar3=e.g. 6-60C aryl, 5-60C heteroaryl, 6-30C aryloxy or 6-60C arylamine (both optionally substituted by deuterium, halo, amino, nitrile, nitro, 1-20C alkyl group, 2-20C alkenyl, 1-20C alkoxy, 3-30C cycloalkyl, 2-30C heterocycloalkyl, 6-60C aryl, 6-20C aryl substituted by deuterium or 3-60C heteroaryl), 1-50C alkyl (optionally substituted by 1-20C alkyl, 2-20C alkenyl, 1-20C alkoxy, 6-20C aryl optionally substituted by deuterium, 8-20C arylalkyl, 8-20C arylalkenyl, 5-20C heterocyclyl, nitrile or acetylene), at least one of Ar1-Ar3 contains deuterium;    R1,R2=e.g. H, deuterium, halo, nitro, nitrile, amino, 6-60C aryl (optionally substituted by deuterium, halo, amino, nitrile, nitro, germanium or 5-20C heterocyclyl), 5-60C heteroaryl (optionally substituted by deuterium, halo, 1-20C alkyl, 2-20C alkenyl, 1-20C alkoxy, 8-20C arylamine, 6-60C aryl, 6-20C aryl substituted by deuterium, 8-20C arylalkyl, 8-20C arylalkenyl, 5-20C heterocyclyl, nitrile or acetylene) containing O, N or S, 1-30C alkoxy (optionally substituted by deuterium, halo, amino, nitrile, nitro, 1-20C alkyl, 2-20C alkenyl, 1-20C alkoxy, 3-30C cycloalkyl, 2-30C heterocycloalkyl, 6-60C aryl, 6-20C aryl substituted by deuterium, or 3-60C heteroaryl), 6-30C aryloxy (optionally substituted by deuterium, halo, amino, nitrile, nitro, 1-20C alkyl, 2-20C alkenyl, 1-20C alkoxy, 3-30C cycloalkyl, 2-30C heterocycloalkyl, 6-60C aryl, 6-20C aryl substituted by deuterium or 3-60C heteroaryl), or 1-50C alkyl (optionally substituted by 1-20C alkyl, 2-20C alkenyl, 1-20C alkoxy, 6-20C aryl, 6-20C aryl substituted by deuterium, 8-20C arylalkyl, 8-20C arylalkenyl, 5-20C heterocyclyl, nitrile or acetylene);    or R1+R2+adjacent group=optionally saturated aliphatic ring or hetero ring;    L=6-60C arylene or 5-60C heteroarylene (both optionally substituted by nitro, nitrile, halo, alkyl, alkoxy or amino);    a=0-4;    b=0-3;and    c=0-2.    Full definitions are given in "DEFINITIONS - Full Definitions" section. INDEPENDENT CLAIMS are included for the following:    (1) organic electric device, which consists of organic layer containing the compound (I) provided between electrodes; and    (2) composition for organic electric device, which contains mixture of the compounds (I).