@article{high_rego_jakubikova_2016, title={Quantum Dynamics Simulations of Excited State Energy Transfer in a Zinc-Free-Base Porphyrin Dyad}, volume={120}, ISSN={["1520-5215"]}, DOI={10.1021/acs.jpca.6b05739}, abstractNote={Rational design of artificial light-harvesting molecular architectures entails building systems that absorb strongly in the visible and near-IR region of the electromagnetic spectrum and also funnel excited state energy to a single site. The ability to model nonadiabatic processes, such as excited-state energy transfer (EET), that occur on a picosecond time scale can aid in the development of novel artificial light-harvesting arrays. A combination of density functional theory (DFT), time-dependent DFT, tight-binding molecular dynamics, and quantum dynamics is employed here to simulate EET in the ZnFbΦ dyad, a model artificial light-harvesting array that undergoes EET with an experimentally measured rate constant of (3.5 ps)-1 upon excitation at 550 nm in toluene [ Yang et al. J. Phys. Chem. B 1998 , 102 , 9426 - 9436 ]. We find that to successfully simulate the EET process, it is important to (1) include coupling between nuclear and electronic degrees of freedom in the QD simulation, (2) account for Coulomb coupling between the electron and hole wavepackets, and (3) parametrize the extended Hückel model Hamiltonian employed in the QD simulations with respect to the DFT.}, number={41}, journal={JOURNAL OF PHYSICAL CHEMISTRY A}, author={High, Judah S. and Rego, Luis G. C. and Jakubikova, Elena}, year={2016}, month={Oct}, pages={8075–8084} }
 @article{high_virgil_jakubikova_2015, title={Electronic Structure and Absorption Properties of Strongly Coupled Porphyrin-Perylene Arrays}, volume={119}, ISSN={["1520-5215"]}, DOI={10.1021/acs.jpca.5b05600}, abstractNote={Porphyrin-perylene arrays are ideal candidates for light-harvesting systems capable of panchromatic absorption. In this work, we employ density functional theory (DFT) and time-dependent DFT to investigate the unique UV-vis absorption properties exhibited by a series of ethynyl-linked porphyrin-perylene arrays that were previously synthesized and characterized spectroscopically [Chem. Commun. 2014, 50, 14512-5]. We find that the ethynyl linker is responsible for strong electronic coupling of porphyrin and perylene subunits in these systems. Additionally, these arrays exhibit a low barrier to rotation around the ethynyl linker (<1.4 kcal/mol per one perylene substituent), which results in a wide range of molecular conformations characterized by different porphyrin-perylene dihedral angles being accessible at room temperature. The best match between the calculated and experimental UV-vis spectra is obtained by averaging the calculated UV-vis spectra over the range of conformations defined by the porphyrin-perylene dihedral angles. Finally, our calculations suggest that the transitions in the lower energy region (550-750 nm) can be assigned to the excitations originating from the porphyrin subunit; the mid-energy region transitions (450-550 nm) are assigned to the perylene-centered excitations, while the high-energy transitions (350-450 nm) involve contributions from both porphyrin and perylene subunits.}, number={38}, journal={JOURNAL OF PHYSICAL CHEMISTRY A}, author={High, Judah S. and Virgil, Kyle K. and Jakubikova, Elena}, year={2015}, month={Sep}, pages={9879–9888} }