Time-dependent density functional theory (TD-DFT) and correlated ab initio methods have been applied to explore the electronically excited states of vitamin B(12) (cyanocobalamin or CNCbl). Different experimental techniques have been used to probe the excited states of CNCbl, revealing many issues that remain poorly understood from an electronic structure point of view. Due to its efficient sca...

The exciton scattering (ES) approach attributes excited electronic states in quasi-1D branched polymer molecules to standing waves of quantum quasiparticles (excitons) scattered at the molecular vertices. We extract their dispersion and frequency-dependent scattering matrices at termini, ortho, and meta joints for pi-conjugated phenylacetylene-based molecules from atomistic time-dependent densi...

The electronic structure relevant to low spin (LS)↔high spin (HS) transitions in Fe(II) coordination compounds with a FeN6 core are studied. The selected [Fe(tz)6]2+ (1) (tz = 1H-tetrazole), [Fe(bipy)3]2+ (2) (bipy = 2,2'-bipyridine), and [Fe(terpy)2]2+ (3) (terpy = 2,2':6',2″-terpyridine) complexes have been actively studied experimentally, and with their respective mono-, bi-, and tridentate ...

In an effort to design deep-blue light emitting materials for use in OLEDs, the optical and electronic properties of a series tetraarylbenzobis[1,2- d :4,5- ′]oxazole (BBO) cruciforms were evaluated using density functional theory (DFT) time-dependent DFT (TD-DFT).

Coinage metal cyanides (MCN) form photoluminescent 1D coordination polymers. The decoration of these chains with amine and phosphine ligands shifts the wavelength for photoluminescence into the visible region. Density-functional theory (DFT) and time-dependent DFT (TD-DFT) calculations of zigzag and helical models of decorated chains are used to show that the transitions that contribute to the ...

In this study, we shed light on the initial addition of hydroxyl radicals (HO˙) to multiple carboxylated and hydroxylated benzene compounds in aqueous-phase advanced oxidation processes (AOPs). We analyze the experimentally measured transient spectra near neutral pH using quantum mechanical-based time-dependent density functional theory (TD-DFT). The ab initio DFT method was first used to find ...

The accuracies of the excited-state dipole and quadrupole moments obtained by TD-DFT are assessed by considering 16 different exchange-correlation functionals and more than 30 medium and large molecules. Except for excited-state presenting a significant charge-transfer character, a relatively limited dependency on the nature of the functional is found. It also turns out that while DFT ground-st...