The influence of temperature on dynamic grating recording in pure azobenzene derivative liquid crystalline molecules is studied. The liquid crystalline system consisted of photochromic molecules of 4-alkyl-4'-alkoxyazobenzenes with different length of substituents, showing nematic liquid crystalline properties close to the room temperature (from T = 32 degrees C). Holographic recording of phase-type gratings was performed in a Degenerate Two Waves Mixing setup, additionally equipped with heating and temperature stabilizing system. For the samples excitation continuous wavelength was used. Explanation of dynamic grating formation is proposed. (C) 2011 Elsevier B.V. All rights reserved.