Intramolecular reorganization energy in zinc phthalocyanine and its fluorinated derivatives: a joint experimental and theoretical study

Abstract

We report a high-resolution gas-phase UPS spectrum of zinc phthalocyanine (ZnPc) together with a detailed analysis of the vibronic structure of the first ionization band, showing that presents the lowest value of the intramolecular reorganization energy experimentally reported for a molecular organic semiconductor.

Molecular Crystal Engineering: Tuning Organic Semiconductor from p‐type to n‐type by Adjusting Their Substitutional Symmetry

“…In our F x MePcs (Me = Cu, Zn; x = 0, 4, 8, 16) system, the Huang-Rhys factors S for electrons and holes are defined as S electron and S hole , respectively. [22] Our calculated values of E pol for holes in F x ZnPcs (x = 0, 4,8,16) are in close agreement with those obtained from joint experimental and theory [23] work considering the relationship of E pol = 1/2λ reorg (λ reorg : reorganization energy), [24] suggesting reliability of the method chosen. But S electron is shown to increase than decrease with fluoridation.…”

Theoretical study of stability and charge-transport properties of coronene molecule and some of its halogenated derivatives: A path to ambipolar organic-based materials?

“…Note also that: (i) previous estimates of reorganization energies for coronene at the B3LYP/6-311++G(d,p) level agrees within 10% or our values; 72 and (ii) the use of a more sophisticated although more costly functional (the double-hybrid B2π -PLYP model, specially devised for accurately dealing with π -conjugated systems of any type 73 ) only slightly change the absolute values of e ·− and h ·+ , being now of 128 and 162 meV, respectively, still keeping a similar ratio (0.79). We also observe that upon halogenation, both h ·+ or e ·− increase, as it was also observed before for partially substituted tetracene molecules 74 or for larger phthalocyanine systems, 75 although the ratio h ·+ / e ·− is not largely affected, being always within the 0.7-1.0 range of values and thus favouring an ambipolar transport (once and again, if all other factors remain the same).…”

Charge transport and prototypical optical absorptions in functionalized zinc phthalocyanine compounds: A density functional study

“…The adiabatic and vertical ionization potentials (IP a and IP v ) of ZnPc were found to be 6.35 and 6.37 eV, respectively, which are in perfect agreement with the experimental value of 6.37 eV as reported by Berkowitz. () Upon fluorination, ionization potential is found to be increased by ∼1.4 eV, which is of the similar order as compared to the experimental data reported by Schwarze et al, and as listed in the Table , the computed value of IP v (IP a ) of F 16 ZnPc is 7.84 (7.79) eV, which is close to the theoretical value (7.57 eV) reported by Liao et al but almost ∼1.1 eV greater than the computed value (∼6.75 eV) reported by Bredas et al() This overestimation in IP value, as we surmise, is the effect of LANL2DZ functional, because a recalculation of IP for F 16 ZnPc at B3LYP/6‐31G(d,p) provides exactly same theoretical value as reported by Bredas et al() Moreover, the values of IPs are found to follow the order (CN) 8 ZnPc > F 16 ZnPc > Cl 16 ZnPc > Br 16 ZnPc > I 8 ZnPc > ZnPc. Similarly, EA a and EA v of ZnPc at the performed computational level were found to be 2.10 and 2.00 eV, which is a little larger (∼0.4 eV) than the previous theoretical value,() and for F 16 ZnPc, electron affinity which is close agreement with that reported earlier increases in magnitude by an order of ∼1.5 eV.…”