PChem Seminar – Brooke Bonar

About the event

Speaker: Brooke Bonar, PhD Student

Group: Dr. Kirk Peterson

Title: Spinor-based relativistic actinide thermochemistry: NpX+/0/- and PuX+/0/- (X = F, Cl, Br, I)

Abstract: A spinor-based coupled cluster approach is applied to NpX+/0/- and PuX+/0/- (X=F, Cl, Br, I) molecules to calculate bond dissociation energies (BDEs), ionization energies (IE), and electron affinities (EA). Results include variational spin-orbit (SO) effects at the orbital level in all calculations, rather than as an additive contribution. This approach exploits the quantum number W, which reduces the multireference nature of unpaired f-electrons in actinide systems. This work uses systematic sequencies of uncontracted correlation consistent basis sets with extrapolations to the complete basis set (CBS) limits, additive contributions including core-valence electron correlation effects, and the accounting of errors due to the two-electron SO treatment in the Exact 2-component (X2C) calculations rather than the full Dirac-Coulomb-Gaunt Hamiltonian. The 0K BDEs of NpF, NpCl, NpBr, and NpI were determined to be 149.0 kcal/mol, 110.4 kcal/mol, 94.9 kcal/mol, and 76.6 kcal/mol, respectively. The 0K BDEs of PuF, PuCl, PuBr, and PuI are significantly smaller at 133.1 kcal/mol 93.1 kcal/mol, 76.6 kcal/mol, and 53.9 kcal/mol, respectively. Ionization potentials and electron affinities are also reported. This talk will provide an introduction to spinor-based calculations and present NpX+/0/- and PuX+/0/- thermochemical results in the broader context of actinide halide thermochemistry.