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Highly accurate potential energy surface for the He-H-2 dimer 

Bakr, Brandon W.; Smith, Daniel G. A.; Patkowski, Konrad; Brandon W. Bakr, Daniel G. A. Smith, and Konrad Patkowski (2020-01-16)
A new highly accurate interaction potential is constructed for the He–H2 van der Waals complex. This potential is fitted to 1900 ab initio energies computed at the very large-basis coupled-cluster level and augmented by ...

Integral approximations in ab initio, electron propagator calculations 

Flores-Moreno, Roberto; Ortiz, J.V. (2021-01-26)
Treatments of interelectronic repulsion that avoid four-center integrals have been incorporated in ab initio, electron-propagator calculations with diagonal self-energy matrices. Whereas the formal scaling of arithmetic ...

The interaction-induced dipole of H-2-H: New ab initio results and spherical tensor analysis 

Lee, Hua-Kuang; Li, Xiaoping; Miliordos, Evangelos; Hunt, Katharine L.C.; https://orcid.org/0000-0003-3471-7133 (2020-04-08)
We present numerical results for the dipole induced by interactions between a hydrogen molecule and a hydrogen atom, obtained from finite-field calculations in an aug-cc-pV5Z basis at the unrestricted coupled-cluster level ...

Interpretation of the photoelectron spectra of superalkali species: Li3O and Li3O- 

Zein, S.; Ortiz, J. V. (2020-10-02)
The present paper deals with the interpretation of the photoelectron spectrum of the Li3O-. After several failed attempts to attribute all of the observed peaks in the experimental spectrum to anionic species, neutral ...

Interpretation of the photoelectron spectra of superalkali species: Na3O and Na3O- 

Zein, S; Ortiz, J. V.; Ortiz, Joseph Vincent (2020-08-20)
Recently measured photoelectron spectra of the Na3O- anion have been interpreted with the aid of ab initio electron propagator calculations. As in the case of the Li3O-, we propose that the photoionization of ground and ...

OH3- and O2H5- double Rydberg anions: Predictions and comparisons with NH4- and N2H7- 

Melin, Junia; Ortiz, J.V. (2021-01-26)
A low barrier in the reaction pathway between the double Rydberg isomer of OH3 − and a hydride-water complex indicates that the former species is more difficult to isolate and characterize through anion photoelectron ...

On the accuracy of explicitly correlated coupled-cluster interaction energies - have orbital results been beaten yet? 

Patkowski, Konrad (2020-08-20)
The basis set convergence of weak interaction energies for dimers of noble gases helium through krypton is studied for six variants of the explicitly correlated, frozen geminal coupled-cluster singles, doubles, and ...

Partial photoionization cross sections of and Rydberg radicals 

Velasco, A.M.; Lavin, C.; Martin, I.; Melin, J.; Ortiz, J.V. (2021-01-26)
ammonium and oxonium Rydberg radicals from the outermost, occupied orbitals of their respective ground states are reported. These properties are known to be relevant in photoelectron dynamics studies. For the present ...

Platinum, gold, and silver standards of intermolecular interaction energy calculations 

Kodrycka, Monika; Patkowski, Konrad; https://orcid.org/0000-0002-4468-207X (2020-03-10)
High-accuracy noncovalent interaction energies are indispensable as data points for potential energy surfaces and as benchmark values for improving and testing more approximate approaches. The preferred algorithm (the gold ...

Quasiparticle virtual orbitals in electron propagator calculations 

Flores-Moreno, Roberto; Ortiz, J.V. (2021-01-26)
The computational limits of accurate electron propagator methods for the calculation of electron binding energies of large molecules are usually determined by the rank of the virtual orbital space. Electron density ...

A Remodeled Protein Arginine Methyltransferase 1 (PRMT1) Generates Symmetric Dimethylarginine 

Gui, Shanying; Gathiaka, Symon; Li, Jun; Qu, Jun; Acevedo, Orlando; Hevel, Joan M. (2020-07-24)
Protein arginine methylation is emerging as a significant post-translational modification involved in various cell processes and human diseases. As the major arginine methylation enzyme, protein arginine methyltransferase ...

Second-order, two-electron Dyson propagator theory: Comparisons for vertical double ionization potentials 

Ida, T.; Ortiz, J.V. (2021-01-26)
The second-order, two-electron Dyson propagator is derived using superoperator theory with a spin-adapted formulation. To include certain ladder diagrams to all orders, the shifted-denominator SD2 approximation is made. ...

Sequential addition of H2O, CH3OH, and NH3 to Al3O3-: A theoretical study 

Guevara-Garcia, Alfredo; Martinez, Ana; Ortiz, J.V. (2021-01-26)
Photoelectron spectra of two species, Al3O3(H2O)(2)(-) and Al3O3(CH3OH)(2)(-), that are produced by the addition of two water or methanol molecules to Al3O3- are interpreted with density-functional geometry optimizations ...

Spin splittings from first-order symmetry-adapted perturbation theory without single-exchange approximation 

Waldrop, Jonathan; Patkowski, Konrad; 0000-0003-0442-193X; 0000-0002-4468-207X (2020-05-20)
The recently proposed spin-flip symmetry-adapted perturbation theory (SF-SAPT) first-order exchange energy [Patkowski et al., J. Chem. Phys. 148, 164110 (2018)] enables the standard open-shell SAPT approach to treat arbitrary ...

Subunit D of RNA Polymerase from Methanosarcina acetivorans Contains Two Oxygen-labile [4Fe-4S] Clusters IMPLICATIONS FOR OXIDANT-DEPENDENT REGULATION OF TRANSCRIPTION 

Lessner, Faith H.; Jennings, Matthew E.; Hirata, Akira; Duin, Eduardus C.; Lessner, Daniel J. (2020-08-20)
Subunit D of multisubunit RNA polymerase from many species of archaea is predicted to bind one to two iron-sulfur (Fe-S) clusters, the function of which is unknown. A survey of encoded subunit D in the genomes of sequenced ...

Surface Green’s function calculations: A nonrecursive scheme with an infinite number of principal layers 

Kletsov, Aleksey; Dahnovsky, Yuri; Ortiz, J.V. (2021-01-26)
A novel computational method for a surface Green’s function matrix is introduced for the calculation of electrical current in molecular wires. The proposed nonrecursive approach includes an infinite number of principal ...

Two-photon imaging of Zn2+ dynamics in mossy fiber boutons of adult hippocampal slices 

Khan, Mustafa; Goldsmith, Christian R.; Huang, Zhen; Georgiou, John; Luyben, Thomas T.; Roder, John C.; Lippard, Stephen J.; Okamoto, Kenichi (2020-01-16)
Mossy fiber termini in the hippocampus accumulate Zn2+, which is released with glutamate from synaptic vesicles upon neural excitation. Understanding the spatiotemporal regulation of mobile Zn2+ at the synaptic level is ...

Valence and diffuse-bound anions of noble-gas complexes with uracil 

Streit, Livia; Dolgounitcheva, O.; Zakrzewski, V. G.; Ortiz, J. V.; Ortiz, Joseph Vincent (2020-08-20)
Valence-bound (VB) and diffuse-bound (DB) anions of noble-gas (Ar, Kr, and Xe) complexes with uracil have been studied with ab initio methods. MP2 optimizations revealed minima corresponding to anions of both kinds in ...