Figure 4.

(Top row) Ground-state geometries of three GaCl₃–phosphine complexes obtained from DFT calculations (see below): (a) GaCl₃ complexed with triethylphosphine, used as model for GaCl₃ complexed with trioctylphosphine (GaCl₃–TOP), (b) GaCl₃ complexed with triphenylphosphite (GaCl₃–TPP), and (c) GaCl₃ complexed with diphenylphosphine (GaCl₃–DPP). (Middle row) TEM images of product NCs obtained after reaction of Cu_2–xS NCs with (d) GaCl₃–TOP at 100 °C, (e) GaCl₃–TPP at 100 °C, and (f) GaCl₃–DPP at 50 °C. Black arrows indicate intraparticle contrast in the NCs reacted with GaCl₃–TPP. Top-right insets show the corresponding ED patterns. Bottom row (g–i) shows the corresponding azimuthally integrated ED patterns. Reference bars in (h,i) are calculated patterns based on the wurtzite CuGaS₂ crystals structure,⁴⁴ and reference bars in (g) are based on the low-chalcocite Cu_2–xS crystal structure.³⁴