We derive and implement symmetry-projected Hartree-Fock-Bogoliubov (HFB) equations apply them to the molecular electronic structure problem. All symmetries (particle number, spin, spatial, complex conjugation) are deliberately broken restored in a self-consistent variation-after-projection approach. show that resulting method yields comprehensive black-box treatment of static correlations with effective one-electron (mean-field) computational cost. The ensuing wave function is multireference...

The singlet electronic potential energy surfaces for the simplest Criegee intermediate CH2OO are computed over a two-dimensional reduced subspace of coordinates, and utilized to simulate photo-initiated dynamics on S2 (B) state leading dissociation multiple coupled excited states. adiabatic potentials evaluated using dynamically weighted state-averaged complete active space self-consistent field theory. Quasi-diabatic states constructed from by maximizing charge separation between then...

Coupled binuclear copper oxide cores are present in the active sites of some very common metalloenzymes found most living organisms. The correct theoretical description interconversion between two dominant structural isomers this core, namely, side-on μ-η2:η2-peroxodicopper(II) and bis(μ-oxo)-dicopper(III), is challenging since it requires a method that can provide balanced static dynamic correlations. We investigate problem using our recently developed projected Hartree–Fock (PHF). Here,...

An efficient approach for synthesizing flavanones and aza-flavanones from their respective 2′-hydroxy- 2′-aminochalcones via halogen bonding (XB) is shown. The DFT studies also supported the catalytic action of XB.

We develop, implement, and apply a quadratically convergent complex multiconfigurational self-consistent field method (CMCSCF) that uses the scaling theorem of Aguilar, Balslev, Combes within framework (MCSCF) in order to theoretically investigate resonances originated due scattering low-energy electron off neutral or an ionic target (atomic molecular). The need scale electronic coordinates Hamiltonian as prescribed requires use modified second quantization algebra suitable for biorthonormal...

Determination of high-dimensional potential energy surfaces (PESs) and nonadiabatic couplings have always been quite challenging. To this end, machine learning (ML) models, trained with a finite set ab initio data, allow accurate prediction such properties. express the PESs in terms atomic contributions is cornerstone any ML based technique because it can be easily scaled to large systems. In work, we constructed high fidelity coupling at CASSCF level data using technique, namely,...

Abstract We present a complex multiconfigurational self‐consistent field (CMCSCF)‐based approach to investigate electron‐atom scattering resonances. It is made possible by the use of second quantization algebra adapted for biorthogonal spin orbitals, which has been applied develop quadratically convergent CMCSCF method. To control convergence correct stationary point, modified step‐length algorithm introduced. Convergence tolerance 1.0 × 10 −10 a.u. energy gradient found be typically within...

The reaction of the chloro-bridged dimeric precursor [{(p-cym)Ru(II)Cl}(μ-Cl)]2 (p-cym = p-cymene) with bridging ligand 3,6-bis(3,5-dimethylpyrazolyl)-1,2,4,5-tetrazine (bpytz) in ethanol results formation dinuclear complex [{(p-cym)Ru(II)Cl}2(μ-bpytz˙(-))](+), [1](+). tetrazine is reduced to anion radical (bpytz˙(-)) which connects two Ru(II) centres. Compound [1](PF6) has been characterised by an array spectroscopic and electrochemical techniques. character confirmed magnetic moment...

Negative-ion resonances are important metastable states that result from the collision between an electron and a neutral target. The course of many chemical processes in nature is often dictated by how intermediate resonance state falls apart. This article reports on development propagator (EP) based Hamiltonian Ĥ perturbed complex absorbing potential (CAP) multiconfigurational self-consistent field (MCSCF) initial to study these resonances. Perturbation CAP makes amenable bound-state method...

The effect of N-heterocyclic carbene in palladium–tin heterobimetallic catalysis is elucidated through the C3–H functionalization indole.

We have devised a hybrid quantum-classical scheme utilizing machine-learned potential energy surfaces (PES), which circumvents the need for explicit computation of nonadiabatic coupling elements. The quantities necessary to account effects are directly obtained from PESs. simulation dynamics is based on fewest-switches surface-hopping method. applied this model photodissociation both N-O and O-O bonds in conformer peroxynitric acid (HO

A simple one-step deposition–precipitation method was used to synthesize highly active and well-defined CuNi alloy bimetallic nanoparticles supported on h-BN/g-C3N4. The nanocomposite applied for hydrogen gas evolution via seawater splitting photocatalytic chloramphenicol (CHP) removal. Through TEM synchrotron studies, the formation of uniform distribution h-BN/g-C3N4 surface observed. EXAFS analysis verified successful alloy, while XPS XANES spectra showed that are in a metallic state....

It has been recognized that CBr4 can give rise to a noncovalent interaction known as halogen bond (XB). was found catalyze, in terms of XB formation, the transformation 2′-aminochalcone aza-flavanone through an intramolecular Michael addition reaction. The impact and resulting yield exhibited pronounced dependence on characteristics solvent. Notably, yields 88% ethanol 33% DMSO were achieved, while merely trace amount product detected benzene. In this work, we use computational modeling...

The transient negative-ion resonances found in scattering experiments are important intermediates many chemical processes. These metastable states correspond to the continuum part of Hamiltonian projectile-target composite system. Usual bound-state electronic structure methods not applicable for these. In this work, we develop a subspace-projection method connection with an electron propagator (EP) defined terms complete-active-space self-consistent-field initial state. target (Ĥ) is...

Views Icon Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Twitter Facebook Reddit LinkedIn Tools Reprints and Permissions Cite Search Site Citation Kousik Samanta, Danny L. Yeager; Investigation of electron-atom/molecule scattering resonances: Two complex multiconfigurational self-consistent field approaches. AIP Conference Proceedings 22 January 2015; 1642 (1): 239–242. https://doi.org/10.1063/1.4906661 Download citation file: Ris (Zotero) Reference...