Organic (mono)radicals where the singly occupied molecular orbital (SOMO) is energetically below highest (HOMO) level have recently attracted much interest. A clear understanding of electronic factors that lead to this energetic SOMO/HOMO inversion (SHI) would be desirable aid rational design SHI radicals with high stability and other desired properties. The govern in known are studied computat...

Thirty two differently substituted siloles 1a-1p and 1,4-disilacyclohexa-2,5-dienes 2a-2p were investigated by quantum chemical calculations using the PBE0 hybrid density functional theory (DFT) method. The substituents included σ-electron donating and withdrawing, as well as π-electron donating and withdrawing groups, and their effects when placed at the Si atom(s) or at the C atoms were exami...

An extensive database of spectroscopic properties of molecules from ab initio calculations is used to design molecular complexes for use in tandem solar cells that convert two photons into a single electron-hole pair, thereby increasing the output voltage while covering a wider spectral range. Three different architectures are considered: the first two involve a complex consisting of two dye mo...

The hexanuclear thioguanidine mixed-valent copper complex cation [Cu6 (NGuaS)6 ]+2 (NGuaS = o-SC6 H4 NC(NMe2 )2 ) and its oxidized/reduced states are theoretically analyzed by means of density functional theory (DFT) (TPSSh + D3BJ/def2-TZV (p)). A detailed bonding analysis using overlap populations is performed. We find that a delocalized Cu-based ring orbital serves as an acceptor for donated ...

The lack of detailed experimental controls has been one of the major obstacles hindering progress in molecular electronics. While large fluctuations have been occurring in the experimental data, specific details, related mechanisms, and data analysis techniques are in high demand to promote our physical understanding at the single-molecule level. A series of modulations we recently developed, b...

Organic radicals with fluorescence from doublet-spin energy manifolds circumvent efficiency limits singlet–triplet photophysics in organic light-emitting diodes (OLEDs). The singly occupied molecular orbital (SOMO) enables the higher potential performance. SOMO also presents substantially lower frontier orbitals compared to conventional fluorescent emitters for device operation, which can cause...

Stimulated by the preparation and characterization of the isolated pentagon rule (IPR) violating chlorofullerene: C(60)Cl(8) (Nat. Mater. 2008, 7, 790-794), we have performed a systematic investigation on the structural stabilities, electronic and optical properties of the IPR-violating C(60)X(8) (X = H, F, and Cl) fullerene compounds via density functional theory. The large energy gaps between...

Quantum chemical calculations have been carried out to study the electronic structure of metalated ylides particularly in comparison to their neutral analogues, the bisylides. A series of compounds of the general composition Ph3 P-C-L with L being either a neutral or an anionic ligand were analyzed and the impact of the nature of the substituent L and the total charge on the electronics and bon...

The electrochemical behaviour of the complexes [Re(CO)(3)X(α-diimine)], X = Cl or Br, α-diimine = 1,4-di-tert-butyl-1,4-diaza-1,3-diene, was reinvestigated using cyclic voltammetry accompanied by IR and UV-vis spectroelectrochemistry. While the reduction results in the loss of halide, as necessary for the electrocatalytic activity of related diimine compounds, a reversible oxidation could be ob...

The electronic absorption spectra, ground-state geometries and electronic structures of symmetric and asymmetric squaraine dyes (SQD1-SQD4) were investigated using density functional theory (DFT) and time-dependent (TD-DFT) density functional theory at the B3LYP/6-311++G** level. The calculated ground-state geometries reveal pronounced conjugation in these dyes. Long-range corrected time depend...