Synthesis, Structure and Application of Intramolecularly‐Coordinated Gallium Chalcogenides: Suitable Single‐Source precursors for Ga x Se y Materials

Studies have been focused on the synthesis of N→Ga‐coordinated organogallium selenides and tellurides [L 1 Ga(μ‐Se)] 2 ( 1 ), [L 2 Ga(μ‐Se)] 2 ( 2 ) and [L 1 Ga(μ‐Te)] 2 ( 3 ), respectively, containing either N,C,N‐ or C,N‐chelating ligands L 1, 2 (L 1 is {2,6‐(Me 2 NCH 2 ) 2 C 6 H 3 } − and L 2 is {2‐(Et 2 NCH 2 )‐4,6‐ t Bu 2 ‐C 6 H 2 } − ) 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 L 1 Ga(κ 2 ‐Se 4 ) ( 4 ) was prepared. An unprecedented complex (L 1 Ga) 2 (μ‐Te 2 )(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 Ga 2 Se 3 crystals with different crystallinity according to conditions used. Therefore, compound 2 may be also used as a source of Ga 2 Se 3 in the low‐temperature doping process of Bi 2 Se 3 .