Related papers: Double excitations in molecules
This chapter gives an introduction to qualitative and quantitative topological analyses of molecular electronic transitions. Among the possibilities for qualitatively describing how the electronic structure of a molecule is reorganized upon…
The \textit{ab initio} approach is used to evaluate the excitation energies of the $2s2p \, ^{2S+1}P_J$ states from the ground state as well as the $2s2p \, ^3P_1 \rightarrow 2s2p \, ^3P_0$ and $2s2p \, ^3P_2 \rightarrow 2s2p \, ^3P_1$…
We give a framework for molecular multiphoton excitation process induced by an optimally designed electric field. The molecule is initially prepared in a coherent superposition state of two of its eigenfunctions. The relative phase of the…
Time-dependent quantum chemical methods coupled to Gaussian basis sets are gaining popularity in modeling the electron dynamics of atoms and molecules interacting with intense laser fields. Two approaches most widely used for this purpose,…
The study of isolated defects in solids is a natural target for classical or quantum embedding methods that treat the defect at a high level of theory and the rest of the solid at a lower level of theory. Here, in the context of…
Coupled cluster methods based exclusively on double excitations are comparatively "cheap" and interesting model chemistries, as they are typically able to capture the bulk of the dynamical electron correlation effects. The trade-off in such…
A fundamental, Quantum Mechanical description of photoactivation of a generic photosensitizer and the ensuing transfer of energy to endogenous oxygen as part of the Type II pathway to photodamage during photodynamic therapy (PDT) is…
A striking example of the need to accurately capture states of double-excitation character in molecules is seen in predicting photo-induced dynamics in small polyenes. Due to the coupling of electronic and nuclear motions,the dark 2$^1$Ag…
We describe our dynamical simulations of the excited states of the carotenoid, neurosporene, following its photoexcitation into the 'bright' (nominally $1^1B_u^+$) state. We employ the adaptive tDMRG method on the UV model of…
In a recent paper [JCTC, 2020, 16, 6098], we introduced a new approach for accurately approximating full CI ground states in large electronic active-spaces, called Tensor Product Selected CI (TPSCI). In TPSCI, a large orbital active space…
We describe the interaction of two two-level atoms in free space with propagating modes of the quantized electromagnetic field, using the time-dependent Heisenberg-Langevin method. For single- photon pulses, we consider the effect of the…
Unravelling two-electron correlation is a long-standing challenge at the heart of few-body quantum physics, underlying correlated phenomena across atomic, molecular and condensed-matter science. In prototypical three-body Coulomb systems,…
We present a linear-response formulation of density cumulant theory (DCT) that provides a balanced and accurate description of many electronic states simultaneously. In the original DCT formulation, only information about a single…
We report ground- and excited-state dipole moments and oscillator strengths (computed in different ``gauges'' or representations) of full configuration interaction (FCI) quality using the selected configuration interaction method known as…
The dual exponential coupled cluster (CC) theory proposed by Tribedi et al.[J. Chem. Theory Comput. 2020, 16, 10, 6317-6328] performs significantly better than the coupled cluster theory with singles and doubles excitations (CCSD) due to…
Addressing both dynamic and static correlation accurately is a primary goal in electronic structure theory. Non-orthogonal configuration interaction (NOCI) is a versatile tool for treating static correlation, offering chemical insights by…
Photoexcitation of the nucleon is studied in the framework of the constituent quark model with nonrelativistic quark-quark interactions. Utilizing the dominance of the pairwise structure of the relevant three-quark potential, the bound and…
Multicomponent systems are defined as chemical systems that require a quantum mechanical description of two or more different types of particles. Non-Born-Oppenheimer electron-nuclear interactions in molecules, electron-hole interactions in…
Collisional heavy ion double charge exchange (DCE) reactions, induced by second order nucleon-nucleon interactions, are shown to provide access to the two-body transition densities of the complementary DCE transitions in the interacting…
Semiconductor nanoplatelets present reduced Auger recombination, giving rise to enhanced multiexciton emission. This virtue makes them good candidates to investigate higher-order carrier dynamics, allowing to extract important excitonic…