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Matteo Bonfanti

Publications and source records attributed to Matteo Bonfanti.

2 recordsLinked to original sources
arXiv2018

Tangent space formulation of the Multi-Configuration Time-Dependent Hartree equations of motion: The projector-splitting algorithm revisited

The derivation of the time-dependent variational equations of the Multi-Configuration Time-Dependent Hartree (MCTDH) method for high-dimensional quantum propagation is revisited from the perspective of tangent space projection methods. In this context, we focus on a recently introduced algorithm [C. Lubich, Appl. Math. Res. eXpress 2015, 311 (2015), B. Kloss et al., J. Chem. Phys. 146, 174107 (2017)] for the integration of the MCTDH equations, which relies on a suitable splitting of the tangent space projection. The new integrator circumvents the direct inversion of reduced density matrices that appears in the standard method, by employing an auxiliary set of non-orthogonal single-particle functions. Here, we formulate the new algorithm and the underlying alternative form of the MCTDH equations in conventional chemical physics notation, in a complementary fashion to the tensor formalism used in the original work. Further, key features of the integration scheme are highlighted.

physics.chem-ph↗
arXiv2011

Few simple rules governing hydrogenation of graphene dots

We investigated binding of hydrogen atoms to small Polycyclic Aromatic Hydrocarbons (PAHs) - i.e. graphene dots with hydrogen-terminated edges - using density functional theory and correlated wavefunction techniques. We considered a number of PAHs with 3 to 7 hexagonal rings and computed binding energies for most of the symmetry unique sites, along with the minimum energy paths for significant cases. The chosen PAHs are small enough to not present radical character at their edges, yet show a clear preference for adsorption at the edge sites which can be attributed to electronic effects. We show how the results, as obtained at different level of theory, can be rationalized in detail with the help of few simple concepts derivable from a tight-binding model of the $π$ electrons.

cond-mat.mes-hall↗