High-Resolution Inner-Shell Photoabsorption and Dissociation of Ozone

Stranges, Stefano; Alagia, Michele; Fronzoni, G.; Decleva, Piero

doi:10.1021/jp003902v

Cited by 20 publications

(36 citation statements)

References 21 publications

(43 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This molecule displays the largest overall shift relative to the experimental spectrum, 92 −2.35 eV in the Pople set, and −1.96 eV with Dunning's set. Apart from this, our calculations confirm the assignment in Ref 92…”

supporting

confidence: 91%

“…: the first spectral feature is due to the terminal oxygens' 1s → π , whereas the second (broad) band is due to both the central oxygens 1s → π and the terminal oxygens' 1s → σ excitations, see also the NTOs inTable 4. The shoulder at 530.7 eV in the experimental spectrum is known to be due to the O1s → σ transition of a small amount of O 2 present in the sample 92.…”

mentioning

confidence: 99%

See 1 more Smart Citation

New and Efficient Equation-of-Motion Coupled-Cluster Framework for Core-Excited and Core-Ionized States

Vidal

Feng

Epifanovsky

et al. 2019

J. Chem. Theory Comput.

217

356

View full text Add to dashboard Cite

 Users may download and print one copy of any publication from the public portal for the purpose of private study or research.  You may not further distribute the material or use it for any profit-making activity or commercial gain  You may freely distribute the URL identifying the publication in the public portal If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim.

show abstract

supporting

confidence: 91%

mentioning

confidence: 99%

New and Efficient Equation-of-Motion Coupled-Cluster Framework for Core-Excited and Core-Ionized States

Vidal

Feng

Epifanovsky

et al. 2019

J. Chem. Theory Comput.

217

356

View full text Add to dashboard Cite

show abstract

“…Apart from this, our calculations confirm the assignment in Ref. 92: the first spectral feature is due to the terminal oxygens' 1s → π , whereas the second (broad) band is due to both the central oxygens 1s → π and the terminal oxygens' 1s → σ excitations, see also the NTOs in Table 4. The shoulder at 530.7 eV in the experimental spectrum is known to be due to the Theory and Computation 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 The final system considered here is adenine, whose NEXAFS and XPS spectra were experimentally recorded in gas-phase by Plekan et al 86 We considered both carbon and nitrogen edges.…”

Section: Statesupporting

confidence: 89%

A New and Efficient Equation-of-Motion Coupled-Cluster Framework for Core-Excited and Core-Ionized States

Vidal¹,

Feng²,

Epifanovsky³

et al. 2019

Preprint

View full text Add to dashboard Cite

We present a fully analytical implementation of the core-valence separation (CVS) scheme for the equation-of-motion (EOM) coupled-cluster singles and doubles (CCSD) method for calculations of core-level states. In the spirit of the original CVS approximation proposed by Cederbaum, Domcke and Schirmer, pure valence excitations are excluded from the EOM target space and the frozen-core approximation is imposed on the reference-state amplitudes and multipliers. This yields an efficient, robust, and accurate EOM-CCSD framework for calculations of excitation and ionization energies as well as state and transition properties (e.g., spectral intensities, natural transition and Dyson orbitals). The accuracy of the new scheme is improved relative to the results obtained applying the CVS only during the solution of the EOM eigenvalue equations. The errors in absolute excitation/ionization energies relative to the experimental reference data are of the order of 0.2{3.0 eV, depending on the K-edge considered and on the basis set used, and the shifts are systematic for each edge.<br>

show abstract

“…The LR-CASSCF approaches based on the CVS approximation and the S&I algorithm are applied to the O 1s core into an σ * orbital 2b 1 as was revealed by QDPTCI [99] and EOM-CCSD calculations [48].…”

Section: Ozonementioning

confidence: 99%

Simulating X‐ray absorption spectra with complete active space self‐consistent field linear response methods

Helmich‐Paris

2020

Int J of Quantum Chemistry

View full text Add to dashboard Cite

In this work, two approaches for simulating X-ray absorption (XA) spectra with the complete active space self-consistent field (CASSCF) linear response (LR) method are introduced. The first approach employs the well-known core-valence separation (CVS) approximation, which is predominantly used by many other electronic structure methods for simulating X-ray spectra. The second ansatz uses the harmonic Davidson algorithm for finding interior eigenvalues that lie close to a target excitation energy shift and virtually solves a shifted-and-inverted (S&I) generalized eigenvalue problem. LR-CASSCF K-edge transition energies are systematically blueshifted though have consistently smaller errors than those of the CAS or restricted active space (RAS) configuration interaction (CI) methods. For simple molecules at which the core hole can only be created at a single site, the state-specific RASSCF or n-electron valence second-order perturbation theory/RASCI gave more accurate principal K-edge excitation energies. If the core hole can be created at multiple sites, the LR-CASSCF approaches perform much better than RASSCF. Moreover, we observed that the LR-CASSCF variants were the only MR methods discussed here that predicted correctly the order of O K-edge features in the ozone molecule and the permanganate ion. The peak separation of edge features in ozone was as accurate as with equation-ofmotion coupled cluster singles and doubles. The error of the CVS approximation turned out to be very system dependent and in some cases amounted up to 1.0 eV for the K-edge excitation energies. Those CVS errors are still acceptable if one considers the observed deviation from the experimental reference by 5-11 eV. The deviations made in the XAS intensities were even more pronounced. CVS and the full S&I oscillator strengths could differ even by a factor of 2.8. Since the S&I approach is at least as efficient as the LR-CASSCF method for valence excitations, future endeavors to improve the accuracy by accounting for dynamic correlation could be built on top of the full S&I approach.

show abstract

High-Resolution Inner-Shell Photoabsorption and Dissociation of Ozone

Cited by 20 publications

References 21 publications

New and Efficient Equation-of-Motion Coupled-Cluster Framework for Core-Excited and Core-Ionized States

New and Efficient Equation-of-Motion Coupled-Cluster Framework for Core-Excited and Core-Ionized States

A New and Efficient Equation-of-Motion Coupled-Cluster Framework for Core-Excited and Core-Ionized States

Simulating X‐ray absorption spectra with complete active space self‐consistent field linear response methods

Contact Info

Product

Resources

About