“…96,97,99 The polymorphic character of MPcs was rst reported by Hamm and Norman in 1948 for CuPc 102 and has since been extensively studied in a number of MPcs. 33,101,[103][104][105][106][107][108][109] MPcs are known to exists in various polymorphic forms identied as a, b, g, d, 3, and x-phases with the metastable a-phase and stable bphase being the most common and commercially signicant. 94,100,101 The phase transition from a to b occurs in most MPc thin-lms through exposure to temperature (200-300 C) 97,99,100,104 or organic solvents, 110,111 and is characterized by a change in tilt angle between planes and the degree of pelectron overlap (Fig.…”