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Polarized infrared reflectivity measurements between 300 and 10 K have been carried out on charge density waves (CDW) conductor blue bronze Tl(0.3)MoO(3). Three important features are observed: (i) A bump at 1155 cm(-1) in the reflectivity spectra of Tl(0.3)MoO(3) at 300 K is a precursor of the Peierls gap due to optical excitations across a pseudogap, and this kind of Peierls-like gap opens gradually with decreasing temperature from 180 to 160 K. (ii) The three sharp modes as "triplet" of infrared reflectivity between 800 and 1000 cm(-1) of Tl(0.3)MoO(3) along [102] axis show red shift compared to K(0.3)MoO(3) and Rb(0.3)MoO(3), which is assigned to the increase of the distance of Mo-O bond with the substitution of thallium ions. (iii) Two peaks at about 514 and 644cm(-1) in the far-infrared reflectivity spectra of Ti(0.3)MoO(3) along [102] direction are suggested to be the electronic transitions from the valence band to the midgap state and from occupied midgap state to the conduction band, respectively. (c) 2008 Elsevier Ltd. All rights reserved.