Dissociative Electron Attachment in C2H via Electronic Resonances

Electronically Excited ◽

<div> <div> <div> <div> Investigation of microwave-activated CH4/H2 plasma used in chemical vapor deposition of diamond revealed the presence of electronically excited C2-(B2Σu+). Using high-level electronic structure methods, we investigate electronic structure of C2H- and suggest possible routes for formation of C2- in the ground (X2Σg+) and excited (B2Σu+) states via electronic resonances. To describe electronically meta-stable states, we employ the equation-of-motion coupled-cluster method augmented by the complex absorbing potential. The resonance wave-functions are analyzed using natural transition orbitals. We identified several resonances in C2H-, including the state that may lead to C2-(B2Σu+). </div> </div> </div> </div>

W4-17: A diverse and high-confidence dataset of atomization energies for benchmarking high-level electronic structure methods

Journal of Computational Chemistry ◽

10.1002/jcc.24854 ◽

2017 ◽

Vol 38 (24) ◽

pp. 2063-2075 ◽

Cited By ~ 51

Author(s):

Amir Karton ◽

Nitai Sylvetsky ◽

Jan M. L. Martin

Keyword(s):

Electronic Structure ◽

High Confidence ◽

Electronic structure of the para-dinitrobenzene radical anion: a combined 2D photoelectron imaging and computational study

Physical Chemistry Chemical Physics ◽

10.1039/c8cp04877k ◽

2018 ◽

Vol 20 (37) ◽

pp. 24019-24026 ◽

Cited By ~ 6

Author(s):

Cate S. Anstöter ◽

Thomas E. Gartmann ◽

Laurence H. Stanley ◽

Anastasia V. Bochenkova ◽

Jan R. R. Verlet

Keyword(s):

Electronic Structure ◽

Ab Initio ◽

Photoelectron Spectroscopy ◽

Radical Anion ◽

Computational Study ◽

Electron Attachment ◽

Dissociative Electron Attachment ◽

Photoelectron Imaging ◽

2D photoelectron spectroscopy combined with high-level ab initio calculations provides insights into the dissociative electron attachment of para-dinitrobenzene.

Nonadiabatic Dynamics Algorithms with Only Potential Energies and Gradients: Curvature-Driven Coherent Switching with Decay of Mixing and Curvature-Driven Trajectory Surface Hopping

10.33774/chemrxiv-2021-8w6fx ◽

2021 ◽

Author(s):

Yinan Shu ◽

Linyao Zhang ◽

Shaozeng Sun ◽

Yudong Huang ◽

Donald Truhlar ◽

...

Keyword(s):

Electronic Structure ◽

Wave Functions ◽

Matrix Elements ◽

Nonadiabatic Dynamics ◽

Time Step ◽

Coupling Matrix ◽

Surface Hopping ◽

New Methods ◽

Curvature Driven

Direct dynamics by mixed quantum–classical nonadiabatic methods is an important tool for understanding processes involving multiple electronic states. Very often, the computational bottleneck of such direct simulation comes from electronic structure theory. For example, at every time step of a trajectory, nonadiabatic dynamics requires potential energy surfaces, their gradients, and the matrix elements coupling the surfaces. The need for the couplings can be alleviated by employing the time derivatives of the wave functions, which can be evaluated from overlaps of electronic wave functions at successive timesteps. However, evaluation of overlap integrals is still expensive for large systems. In addition, for electronic structure methods for which the wave functions or the coupling matrix elements are not available, nonadiabatic dynamics algorithms become inapplicable. In this work, building on recent work by Baeck and An, we propose new nonadiabatic dynamics algorithms that only require adiabatic potential energies and their gradients. The new methods are named curvature- driven coherent switching with decay of mixing (κCSDM) and curvature-driven trajectory surface hopping (κTSH). We show how powerful these new methods are in terms of computer time and good agreement with methods employing nonadiabatic coupling vectors computed in conventional ways. The lowering of the computational cost will allow longer nonadiabatic trajectories and greater ensemble averaging to be affordable, and the ability to calculate the dynamics without electronic structure coupling matrix elements extends the dynamics capability to new classes of electronic structure methods.

SparseMaps—A systematic infrastructure for reduced scaling electronic structure methods. V. Linear scaling explicitly correlated coupled-cluster method with pair natural orbitals

The Journal of Chemical Physics ◽

10.1063/1.4979993 ◽

2017 ◽

Vol 146 (17) ◽

pp. 174108 ◽

Cited By ~ 63

Author(s):

Fabijan Pavošević ◽

Chong Peng ◽

Peter Pinski ◽

Christoph Riplinger ◽

Frank Neese ◽

...

Keyword(s):

Electronic Structure ◽

Cluster Method ◽

Coupled Cluster ◽

Linear Scaling ◽

Coupled Cluster Method ◽

Natural Orbitals ◽

Explicitly Correlated

Solvent tunable photophysics of acridone: a quantum chemical perspective

RSC Advances ◽

10.1039/c5ra27580f ◽

2016 ◽

Vol 6 (22) ◽

pp. 18530-18537 ◽

Cited By ~ 6

Author(s):

Vidisha Rai-Constapel ◽

Christel M. Marian

Keyword(s):

Electronic Structure ◽

Quantum Chemistry ◽

Quantum Chemical ◽

High-level electronic structure methods and quantum chemistry programs have been employed for a thorough investigation of the photophysics of acridone in isolated and solvated states.

Performance of the SCC-DFTB Model for Description of Five-Membered Ring Carbohydrate Conformations: Comparison to Force Fields, High-Level Electronic Structure Methods, and Experiment

Journal of Chemical Theory and Computation ◽

10.1021/ct200789w ◽

2012 ◽

Vol 8 (7) ◽

pp. 2412-2423 ◽

Cited By ~ 18

Author(s):

Shahidul M. Islam ◽

Pierre-Nicholas Roy

Keyword(s):

Electronic Structure ◽

Force Fields ◽

Membered Ring ◽

The quest to uncover the nature of benzonitrile anion

Physical Chemistry Chemical Physics ◽

10.1039/c9cp06484b ◽

2020 ◽

Vol 22 (9) ◽

pp. 5002-5010

Author(s):

Sahil Gulania ◽

Thomas-C. Jagau ◽

Andrei Sanov ◽

Anna I. Krylov

Keyword(s):

Electronic Structure ◽

Anionic states of benzonitrile are investigated by high-level electronic structure methods.

EOM-CC Guide for Fock-Space Travel: The C2 Edition

10.26434/chemrxiv.7368299 ◽

2018 ◽

Author(s):

Sahil Gulania ◽

Thomas-C. Jagau ◽

Anna I. Krylov

Keyword(s):

Electronic Structure ◽

Ionization Potential ◽

Fock Space ◽

Wave Functions ◽

Cluster Method ◽

Coupled Cluster ◽

Space Travel ◽

Electron Detachment ◽

Coupled Cluster Method ◽

Structure Calculations

Despite their small size, C2 species pose a big challenge to electronic structure owing to extensive electronic degeneracies and multi-configurational wave functions leading to a dense manifold of electronic states. We present detailed electronic structure calculations of C2, C2-, and C22- emphasizing spectroscopically relevant properties. We employ double ionization potential (DIP) and ionization potential (IP) variants of equation-of-motion coupled-cluster method with single and double substitutions (EOM-CCSD) and a dianionic reference state. We show that EOM-CCSD is capable of describing multiple interacting states in C2 and C2- in an accurate, robust, and effective way. We also characterize the electronic structure of C22-, which is metastable with respect to electron detachment.

Two Cycling Centers in One Molecule: Communication by Through-Bond Interactions and Entanglement of the Unpaired Electrons

10.26434/chemrxiv.11502486 ◽

2020 ◽

Author(s):

Maxim Ivanov ◽

Sahil Gulania ◽

Anna I. Krylov

Keyword(s):

Electronic Structure ◽

Alkali Metals ◽

Information Science ◽

Electron Attachment ◽

Laser Cool ◽

Cluster Method ◽

Double Electron ◽

Multiple Absorption ◽

Unpaired Electrons ◽

Molecule Communication

<div> <div> <div> Many applications in quantum information science (QIS) rely on the ability to laser-cool molecules. The scope of applications can be expanded if laser-coolable molecules possess two or more cycling centers, i.e., moieties capable of scattering photons via multiple absorption-emission events. Here we employ equation-of-motion coupled-cluster method for double electron attachment (EOM-DEA-CCSD) to study electronic structure of hypermetallic molecules with two alkaline earth metals con- nected by an acetylene linker. We demonstrate that the interaction between two unpaired electrons is weak yet non-negligible, and is reflected in the underlying wavefunction. The electronic structure of the molecules is similar to that of two separated alkali metals, however the interaction between two electrons is largely dominated by through-bond interactions. The communication between the two cycling centers is quantified by the extent of the entanglement of the two unpaired electrons associated with each center. This contribution highlights rich electronic structure of hypermetallic molecules that may advance various applications in QIS and beyond. </div> </div> </div>