Revisiting the Chemistry of the Actinocenes [(η⁸‑C₈H₈)₂An] (An = U, Th) with Neutral Lewis Bases. Access to the Bent Sandwich Complexes [(η⁸‑C₈H₈)₂An(L)] with Thorium (L = py, 4,4′-bipy, <i>t</i>BuNC, R₄phen)

In stark contrast to uranocene, (Cot)₂Th reacts with neutral mono- or bidentate Lewis bases to give the bent sandwich complexes (Cot)₂Th­(L) (L = py, 4,4′-bipy, <i>t</i>BuNC, phen, Me₄phen). DFT calculations in the gas phase show that, for both U and Th, formation of the bent compound (Cot)₂An­(L) should be facile, the linear and bent forms being close in energy

Revisiting the Chemistry of the Actinocenes [(η⁸‑C₈H₈)₂An] (An = U, Th) with Neutral Lewis Bases. Access to the Bent Sandwich Complexes [(η⁸‑C₈H₈)₂An(L)] with Thorium (L = py, 4,4′-bipy, <i>t</i>BuNC, R₄phen)

In stark contrast to uranocene, (Cot)₂Th reacts with neutral mono- or bidentate Lewis bases to give the bent sandwich complexes (Cot)₂Th­(L) (L = py, 4,4′-bipy, <i>t</i>BuNC, phen, Me₄phen). DFT calculations in the gas phase show that, for both U and Th, formation of the bent compound (Cot)₂An­(L) should be facile, the linear and bent forms being close in energy

Finite Temperature Infrared Spectra from Polarizable Molecular Dynamics Simulations

Infrared spectra of biomolecules are obtained from molecular dynamics simulations at finite temperature using the AMOEBA force field. Diverse examples are presented such as <i>N</i>-methylacetamide and its derivatives and a helical peptide. The computed spectra from polarizable molecular dynamics are compared in each case to experimental ones at various temperatures. The role of high-level electrostatic treatment and explicit polarization, including parameters improvements, is highlighted for obtaining spectral sensitivity to the environment including hydrogen bonds and water molecules and a better understanding of the observed experimental bands

Ab Initio Extension of the AMOEBA Polarizable Force Field to Fe²⁺

We extend the AMOEBA polarizable molecular mechanics force field to the Fe²⁺ cation in its singlet, triplet, and quintet spin states. Required parameters are obtained either directly from first principles calculations or optimized so as to reproduce corresponding interaction energy components in a hexaaquo environment derived from quantum mechanical energy decomposition analyses. We assess the importance of the damping of point-dipole polarization at short distance as well as the influence of charge-transfer for metal-water interactions in hydrated Fe²⁺; this analysis informs the selection of model systems employed for parametrization. We validate our final Fe²⁺ model through comparison of molecular dynamics (MD) simulations to available experimental data for aqueous ferrous ion in its quintet electronic ground state