Synthesis, Structure and Application of Intramolecularly-Coordinated Gallium Chalcogenides: Suitable Single-Source...

Studies have been focused on the synthesis of N→Ga-coordinated organogallium selenides and tellurides [L¹ Ga(μ-Se)]₂ (1), [L² Ga(μ-Se)]₂ (2) and [L¹ Ga(μ-Te)]₂ (3), respectively, containing either N,C,N- or C,N-chelating ligands L^1, 2 (L¹ is {2,6-(Me₂ NCH₂ )₂ C₆ H₃ }^- and L² is {2-(Et₂ NCH₂ )-4,6-tBu₂ -C₆ H₂ }^- ) having Ga/E (E=Se or Te) atoms in 1/1 ratio. To change the Ga/E ratio, an unusual N→Ga-coordinated organogallium tetraselenide L¹ Ga(κ² -Se₄ ) (4) was prepared. An unprecedented complex (L¹ Ga)₂ (μ-Te₂ )(μ-Te) (5), as the result of the non-stability of 3, was also isolated. Compound 2 is a suitable single-source precursor for the preparation of amorphous GaSe thin films by the spin coating. Moreover, simple heating of an octadecylamine solution of 2 provided, after work up, monoclinic Ga₂ Se₃ crystals with different crystallinity according to conditions used. Therefore, compound 2 may be also used as a source of Ga₂ Se₃ in the low-temperature doping process of Bi₂ Se₃ .