Toward a General Formulation of Dispersion Effects for Solvation Continuum Models

We revised the quantum model of Amovilli and Mennucci (J. Phys. Chem. B 1997, 101, 1051) to include the dispersion contribution to the solvation free energy within the framework of continuum models. Our revised formulation makes use of a single adjustable solvent dependent parameter, and it can be readily generalized to different quantum mechanical descriptions. In particular, we made use of DFT and applied the model to investigate dispersion effects on vertical excitation energies within a time-dependent DFT framework. Our findings show that dispersion effects constitute a significant component of the absolute solvent effect but when relative solvent-solvent shifts are considered a cancellation effect is observed

Enchantment and perpetual desire

doi: 10.1177/1470593120961461Dominant perspectives on technology adoption and consumption tend to be cognitive, instrumental, and individualistic. We offer a desire-centered, future-oriented, and culturally grounded alternative model called the Disenchanted Enchantment Model (DEM). Drawing on historical evidence and revised interpretations of theories of enchantment and disenchantment by Weber and Saler, we show that desire is at the heart of technology consumption?s enchantments, and how its fulfilment is temporary, skeptical, and ironic. We provide an important cultural counterbalance to models such as the Technology Acceptance Model, which replace wonder with reason. Instead we theorize the process that drives contemporary technology adoption as centering on desirous senses of wonderment and anticipation. We offer current and recent examples of the DEM process and discuss the implications this model holds for a new understanding of technology, consumption, desire, and broader consumer culture.Peer reviewe

Effective Time-Independent Calculations of Vibrational Resonance Raman Spectra of Isolated and Solvated Molecules Including Duschinsky and Herzberg-Teller Effects

We present a method of modeling vibrational resonance Raman scattering (RRS) spectra of isolated and solvated systems with the inclusion of FranckCondon (FC) and HerzbergTeller (HT) effects and a full account for possible differences between the harmonic potential energy surfaces of the initial and resonant electronic states. It describes fundamentals, overtones, and combination bands and computes the RRS spectrum as a two-dimensional function of the incident and scattered frequencies. The theoretical foundations of the method are described and the differences with other currently available methodologies are outlined. Applications to the phenoxyl radical in the gas phase and indolinedimethine malononitrile (IDMN) in acetonitrile and cyclohexane solution are reported, as well as comparisons with available experimental data

Excited states behavior of nucleobases in solution: insights from computational studies

We review the most significant results obtained in the study of isolated nucleobases in solution by quantum mechanical methods, trying to highlight also the most relevant open issues. We concisely discuss some methodological issues relevant to the study of molecular electronic excited molecular states in condensed phases, focussing on the methods most commonly applied to the study of nucleobases, i.e. continuum models as the Polarizable Continuum Model and explicit solvation models. We analyse how the solvent changes the relative energy of the lowest energy excited states in the Franck-Condon region, their minima and the Conical Intersections among the different states, interpreting the experimental optical spectra, both steady state and time-resolved. Several methods are available for accurately including solvent effects in the Franck-Condon region, and for most of the nucleobases the solvent shift on the different excited states can be considered assessed. The study of the excited state decay, both radiative and non-radiative, in solution still poses instead significant theoretical challenges