Molecular orbital analysis of selected organic p-type and n-type conducting small molecules

Abstract

In this article, the selected series of commercially available p-type and n-type semiconducting small molecules are systematically studied by density functional theory using the B3LYP hybrid functional and 6-311G(2d,p) basis set. The optimal geometries of each molecule in the electronic neutral and corresponding charged states are calculated. The evaluated energies of frontier molecular orbitals and electronic band gaps are mutually compared together with adiabatic electronic intramolecular reorganization energies. The chemical accuracy of the evaluated theoretical quantities is estimated from the comparison with available experimental data.

Heterocycles as Supramolecular Handles for Crystal Engineering: A Case Study with 7-(diethylamino)coumarin Derivatives

“…[39][40][41] Frontier molecular orbital energies were calculated using the As shown in Figure 11, FMO energies for the existing DAC derivatives are mostly centered around 𝐸 ̅ 𝐻𝑂𝑀𝑂 ± 𝜎𝐻𝑂𝑀𝑂 = − 6.29 ± 0.17 eV, which is in the range of values (-6.6 to -4.4 eV) reported for n-type semiconductors. 42 The average LUMO energy is 𝐸 ̅ LUMO ± 𝜎LUMO = − 1.51 ± 0.28 eV, within the range of values (-1.2 to -3.6 eV) reported for p-type semiconductors. This behavior shows that the electronic structure of coumarin derivatives allows not only their use as handles for the design of molecules with programmable aggregation, but also as contributors to the desirable physical properties of the molecular materials built upon it.…”

Heterocycles as supramolecular handles for crystal engineering: a case study with 7-(diethylamino)coumarin derivatives

“…12A, the FMO energies for the existing 7-DAC derivatives are in most of the cases centered around E HOMO ± s HOMO = −6.29 ± 0.17 eV, which is in the range of values (−6.6 to −4.4 eV) reported for n-type semiconductors. 66 Moreover, the average LUMO energy is E LUMO ± s LUMO = −1.51 ± 0.28 eV, within the range of values (−1.2 to −3.6 eV) reported for p-type semiconductors. This ambivalent behavior is illustrated in Fig.…”

“…In optoelectronic materials, the luminescent or semiconducting response of a given molecular material tends to correlate with frontier molecular orbital (FMO) energy values, which serve as proxies of the ionization potential (IP) and electron affinities (EA) of the molecule; IP and EA are critical parameters for candidate discrimination and for the selection of suitable electrodes for the implementation of a given material into an electronic devices such as a diode or a transistor. [63][64][65][66] Frontier molecular orbital energies were calculated using a DFT protocol based on an accurate density functional from the Minnesota family (MN15), a global hybrid functional with excellent performance in scenarios with electron degeneracy, as is the case of organic molecules with extensive p conjugation. Details are provided in the Materials and methods section and the scatter of FMO values for all compounds 1-50 are presented in Fig.…”

Hydrogen-Bond-Promoted Planar Conformation, Crystallinity, and Charge Transport in Semiconducting Diazaisoindigo Derivatives

“…However, the oxidation potentials were not as significantly impacted and all showed highest occupied molecular orbital (HOMO) levels in the range from −5.55 eV to −5.44 eV for typical p-type organic semiconductors. 39,40 According to these values, o-AID and p-AID were expected to give a p-type semiconducting behavior while the n-type property was anticipated to be unstable, because the LUMO was not low enough. 41 The overall bandgaps of o-AID and p-AID were also smaller, compared to that of ID-C.…”