Minimum Energy Conical Intersection Optimization Using DFT/MRCI(2).

The combined density functional theory and multireference configuration interaction (DFT/MRCI) method is a semiempirical electronic structure approach that is both computationally efficient and has predictive accuracy for the calculation of electronic excited states and for the simulation of electronic spectroscopies. However, given that the reference space is generated via a selected-CI procedure, a challenge arises in the construction of smooth potential energy surfaces. To address this issue, we treat the local discontinuities that arise as noise within the Gaussian progress regression framework and learn the surfaces by explicitly incorporating and optimizing a white-noise kernel.

Opening up creative resources: towards age-friendly communities through rhizomatic thinking and doing.

Globally, many complex issues, like the ageing population and health inequalities, require attention. People are experimenting to combat these issues in their local contexts through bigger or smaller networks; however, much of the knowledge about these initiatives remains localised and elitist and omits the voices and perspectives of citizens. This article identifies the characteristics of a more horizontal, emergent and plural epistemology to mobilize knowledge.

Probing the Electronic Manifold of MgCl with Millimeter-Wave Spectroscopy and Theory: (3)Σ and (4)Σ States.

The millimeter/submillimeter spectrum of magnesium chloride (MgCl) has been observed in two new electronic excited states, (3)Σ and (4)Σ, using direct absorption methods. The molecule was synthesized in a mixture of Cl, argon, and magnesium vapor. For the (3)Σ state, multiple rotational transitions were measured in the = 0 level for all six isotopologues (MgCl, MgCl, MgCl, MgCl, MgCl, and MgCl), as well as up to = 13 for MgCl.

A DFT/MRCI Hamiltonian parameterized using only ab initio data. II. Core-excited states.

A newly parameterized combined density functional theory and multi-reference configuration interaction (DFT/MRCI) Hamiltonian, termed core-valence separation (CVS)-QE12, is defined for the computation of K-shell core-excitation and core-ionization energies. This CVS counterpart to the recently reported QE8 Hamiltonian [Costain et al., J.

Time Resolved Quantum Tomography in Molecular Spectroscopy by the Maximal Entropy Approach.

Attosecond science offers unprecedented precision in probing the initial moments of chemical reactions, revealing the dynamics of molecular electrons that shape reaction pathways. A fundamental question emerges: what role, if any, do quantum coherences between molecular electron states play in photochemical reactions? Answering this question necessitates quantum tomography─the determination of the electronic density matrix from experimental data, where the off-diagonal elements represent these coherences. The Maximal Entropy (MaxEnt) based Quantum State Tomography (QST) approach offers unique advantages in studying molecular dynamics, particularly with partial tomographic data.