NOVELTY - An indole-containing compound (I), is new.    USE - New indole-containing compound is used for organic electronic device e.g. organic electroluminescent device, organic solar cell, organophotoreceptor and organic thin-film transistor (all claimed).    ADVANTAGE - The organic electric device containing the indole-containing compound has low driving voltage, improved luminous efficiency and excellent durability.    DETAILED DESCRIPTION - An indole-containing compound of formula (I), is new.    Ar1,Ar2=6-60C aryl optionally substituted by substituent chosen from H, deuterium, halo, amino, nitrile, nitro, 1-20C alkyl, 1-20C alkoxy, 1-20C alkylamino, 1-20C alkylthiophene, 6-20C arylthiopene, 2-20C alkenyl, 2-20C alkynyl, 3-20C cycloalkyl, 6-60C aryl, 6-20C aryl substituted by deuterium, 8-20C arylalkenyl, silane, boron, germanium and 5-20C heterocyclyl, 5-60C heterocyclyl optionally substituted by substituent chosen from H, deuterium, halo, 1-20C alkyl, 2-20C alkenyl, 1-20C alkoxy, 8-20C arylamino, 6-60C aryl, 6-20C aryl substituted by deuterium, 8-20C arylalkyl, 8-20C arylalkenyl, 5-20C heterocyclyl, nitrile and acetylene, 6-30C aryloxy optionally substituted by substituent chosen from H, 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 and 3-60C heteroaryl, or 1-50C alkyl optionally substituted by substituent chosen from 1-20C alkyl, 2-20C alkenyl, 1-20C alkoxy, 6-20C aryl, 2-20C aryl substituted by deuterium, 8-20C arylalkyl, 8-20C arylalkenyl, 5-20C heterocyclyl, nitrile and acetylene;    R1,R2=H, deuterium, halo, nitro, nitrile, amino, 6-60C aryl optionally substituted by substituent chosen from H, deuterium, halo, amino, nitrile, nitro, 1-20C alkyl, 1-20C alkoxy, 1-20C alkylamino, 1-20C alkylthiophene, 6-20C arylthiopene, 2-20C alkenyl, 2-20C alkynyl, 3-20C cycloalkyl, 6-60C aryl, 6-20C aryl substituted by deuterium, 8-20C arylalkenyl, silane, boron, germanium and 5-20C heterocyclyl, 5-60C heteroaryl having O, N, and S, 6-60C arylamino, 1-30C alkoxy, 6-30C aryloxy optionally or 1-50C alkyl;    or R1+R2+neighboring group=(un)saturated aliphatic ring or hetero ring;    a=1-5;and    b=1-5.    "Full Definitions are given in the DEFINITIONS (Full Definitions) field". INDEPENDENT CLAIMS are included for the following:    (1) organic electric device, which includes organic layer containing indole-containing compound (I), an electrode (e1), and an electrode (e2); and    (2) terminal.