Publications

For up-to-date bibliometric statistics (h-index, # of citations, etc.) please visit my public ResearcherID profile: H-5282-2012

in preparation

56. S. Knecht. Relativistic second-order density-matrix renormalization group self-consistent field.
in preparation.

submitted

under revision

accepted/in press

published

2020

55. D. Wehrli, M. Génévriez, S. Knecht, M. Reiher, and F. Merkt. Complete characterization of the 3p Rydberg complex of a molecular ion: MgAr+. I. Observation of the Mg(3pσ)Ar+ B+ state and determination of its structure and dynamics.
J. Chem. Phys., 153, 074310 (2020).

54. F. Aquilante, J. Autschbach, A. Baiardi,   S. Battaglia, V. A. Borin,   L. F. Chibotaru, I. Conti, L. De Vico, M. Delcey, I. Fdez. Galv{\’a}n, N. Ferr\’e, L. Freitag, M. Garavelli, X. Gong, S. Knecht, E. D. Larsson, R.  Lindh,   M. Lundberg, P. {\AA} Malmqvist,   A. Nenov, J. Norell, M. Odelius, M. Olivucci, T. B. Pedersen1, L. Pedraza-Gonz{\’a}lez, Q. M. Phung1, K. Pierloot, M. Reiher, I. Schapiro, J.  Segarra-Martí, F. Segatta, L. Seijo, S.  Sen, D.C. Sergentu, C. J. Stein, L. Ungur, M. Vacher, A. Valentini and V. Veryazov, Modern Quantum Chemistry with [Open]Molcas.
J. Chem. Phys., 152, 214117 (2020).

53. T. Saue, R. Bast, A. S. P. Gomes, H. J. Aa. Jensen, L. Visscher, I. A. Aucar, R. Di Remigio, K. G. Dyall, E. Eliav, E. Fa{\ss}hauer, T. Fleig, L. Halbert, E. D. Hedeg{\aa}rd, B. Helmich-Paris, M. Ilia\v{s}, C. R. Jacob, S. Knecht, J. K. L{\ae}rdahl, M. L. Vidal, M. K. Nayak, M. Olejniczak, J. M. H. Olsen, M. Pernpointner, B. Senjean, A. Shee, A. Sunaga, J. N. P.van Stralen, The DIRAC code for relativistic molecular calculations.
J. Chem. Phys., 152, 204104 (2020).
arXiv: 2002.06121

2019

52. L. Freitag, Y. Ma, A. Baiardi, S. Knecht, M. Reiher, Approximate analytical gradients and nonadiabatic couplings for the state-average density matrix renormalization group self-consistent field method.
J. Chem. Theory Comput., 15, 6724 (2019).
arXiv: 1905.01558

51. I. Fdez. Galv{\’a}n, M. Vacher, A. Alavi, C. Angeli, F. Aquilante, J. Autschbach, J. J. Bao, S. I. Bokarev, N. A. Bogdanov, R. K. Carlson, L. F. Chibotaru, J. Creutzberg, N. Dattani, M. G. Delcey, S. S. Dong, A. Dreuw, L. Freitag, L. M. Frutos, L. Gagliardi, F. Gendron, A. Giussani, L. Gonz{\’a}lez, G. Grell, M. Guo, C. E. Hoyer, M. Johansson, S. Keller, S. Knecht, G. Kova{\v{c}}evi{\’c}, E. K{\”a}llman, G. Li Manni, M. Lundberg, Y. Ma, S. Mai, J. Pedro Malhado, P. \AA\  Malmqvist, P. Marquetand, S. A. Mewes, J. Norell, M. Olivucci, M. Oppel, Q. M. Phung, K. Pierloot, F. Plasser, M. Reiher, A. M. Sand, I. Schapiro, P. Sharma, C. J. Stein, L. K. S{\o}rensen, D. G. Truhlar, M. Ugandi, L. Ungur, A. Valentini, S. Vancoillie, V. Veryazov, O. Weser, T. A. Wesołowski, P.-O. Widmark, S. Wouters, A. Zech, J. P. Zobel, and R. Lindh, OpenMolcas: From source code to insight.
J. Chem. Theory Comput., 15, 5925 (2019).
ChemRxiv. Preprint.

50. P. Sharma, V. Bernales, S. Knecht, D. G. Truhlar and L. Gagliardi, Density matrix renormalization group pair-density functional theory (DMRG-PDFT): Singlet-triplet gaps in polyacenes and polyacetylenes.
Chem. Sci., 10, 1716 (2019).

49. S. Knecht, H. J. Aa. Jensen and T. Saue, Relativistic quantum chemical calculations show that the uranium molecule U2 has a quadruple bond.
Nat. Chem.,11, 40-44 (2019).

2018

48. C. Schilling, M. Altunbulak, S. Knecht, A. Lopes, J. D. Whitfield, M. Christandl, D. Gross, and M. Reiher, Generalized Pauli constraints in small atoms.
Phys. Rev. A 97, 052503 (2018).
arXiv: 1710.03074

JCTC May 2018 issue

47. S. Battaglia, S. Keller, and S. Knecht, An efficient relativistic density-matrix renormalization group implementation in a matrix-product formulation.
J. Chem. Theory Comput., 14, 2353-2369 (2018).
arXiv: 1710.08301

2017

46. Md. M. Alam and K. Deur and S. Knecht and E. Fromager, Combining extrapolation with ghost interaction correction in range-separated ensemble density functional theory for excited states.
J. Chem. Phys., 147, 204105 (2017).
arXiv: 1708.03478

45. R. Spezia, S. Knecht, B. Mennucci, Excited state characterization of carbonyl containing carotenoids: a comparison between single and multi reference descriptions.
Phys. Chem. Chem. Phys., 16, 17156-17166 (2017).
arXiv:1705.01939

44. B. Helmich-Paris and S. Knecht, Laplace-transformed multi-reference second-order perturbation theories in the atomic and active molecular orbital basis.
J. Chem. Phys., 146, 224101 (2017).
arXiv:1703.07204.

43. Y. Ma, S. Knecht, S. Keller, M. Reiher, Second-order self-consistent-field density-matrix renormalization group.
J. Chem. Theory Comput., 13, 2533–2549 (2017).
arXiv:1611.05972.

42. L. Freitag, S. Knecht, C. Angeli, M. Reiher, Multi-reference perturbation theory with Cholesky decomposition for the density matrix renormalization group.
J. Chem. Theory Comput., 13, 451-459 (2017).
arXiv:1608.02006

41. Y. Ma, S. Knecht, M. Reiher, Multiconfigurational effects in theoretical resonance Raman spectra.
ChemPhysChem, 18, 384–393 (2017).

2016

40. S. Knecht, S. Keller, J. Autschbach, M. Reiher, A nonorthogonal state-interaction approach for matrix product state wave functions.
J. Chem. Theory Comput., 12, 5881–5894 (2016).
arXiv:1609.02684

39. A. Almoukhalalati, S. Knecht, H. J. Aa. Jensen, K. Dyall, T. Saue, Electron correlation within the relativistic no-pair approximation.
J. Chem. Phys., 145, 074104 (2016).

38. M. M. Alam, S. Knecht, E. Fromager, Ghost interaction correction in ensemble density-functional theory for excited states with and without range separation.
Phys. Rev. A, 94, 012511 (2016).
arXiv: 1603.05385

37. S. Knecht, E. D. Hedegård, S. Keller, A. Kovyrshin, Y. Ma, A. Muolo, C. J. Stein, M. Reiher, New approaches for ab initio calculations of molecules with strong electron correlation.
Chimia, 70, 244-251 (2016).
arXiv: 1512.09267

36. B. Senjean, E. D. Hedegård, Md. M. Alam, S. Knecht, E. Fromager, Combining linear interpolation with extrapolation methods in range-separated ensemble density-functional theory.
Mol. Phys., 114, 968-981 (2016).
arXiv:1509.08033

2015

35. B. Senjean, S. Knecht, H. J. Aa. Jensen, and E. Fromager, Linear interpolation method in ensemble Kohn-Sham and range-separated density-functional approximations for excited states.
Phys. Rev. A, 92, 012518 (2015).

34. E. D. Hedegaard, S. Knecht, J. S. Kielberg, H. J. Aa. Jensen, and M. Reiher, Density matrix renormalization group with efficient dynamical electron correlation through range separation.
J. Chem. Phys.142, 224108 (2015).

33. A. Shee, S. Knecht, and T. Saue, A theoretical benchmark study of the spectroscopic constants of the very heavy rare gas dimers.
Phys. Chem. Chem. Phys.17, 10978 (2015).

32. E. Hedegård, J. M. Olsen, S. Knecht, J. Kongsted, and H. J. Aa. Jensen, Polarizable Embedding with a Multiconfiguration Short-Range Density Functional Theory Linear Response Method.
J. Chem. Phys.142, 114113 (2015).

31. M. Denis, M. N. Pedersen, H. J. Aa. Jensen, A. Gomes, M. Nayak, S. Knecht, and T. Fleig, Theoretical Study on ThF+, a prospective system in search of time-reversal violation.
New J. Phys.17, 043005 (2015).

30. L. Freitag, S. Knecht, S. F. Keller, M. G. Delcey, F. Aquilante, T. Bondo Pedersen, R. Lindh, M. Reiher, and L. González, Orbital entanglement and CASSCF analysis of the Ru–NO bond in a Ruthenium nitrosyl complex.
Phys. Chem. Chem. Phys., 17, 14383-14392 (2015).

29. T. Dresselhaus, J. Neugebauer, S. Knecht, S. Keller, Y. Ma, and M. Reiher, Self-consistent embedding of density-matrix renormalization group wavefunctions in a density functional environment.
J. Chem. Phys.142, 044111 (2015).
arXiv:1409.1953

28. O. Andreussi, S. Knecht, C. M. Marian, J. Kongsted, and B. Mennucci, Carotenoids and light-harvesting: from DFT/MRCI to the Tamm-Dancoff approximation.
J. Chem. Theory Comput.11, 655-666 (2015).

2014

27. P. Tecmer, A. Gomes, S. Knecht, and L. Visscher, Relativistic Fock-space coupled cluster study of small building blocks of larger uranium complexes.
Communication: J. Chem. Phys.141, 041107 (2014).

26. E. D. Hedegaard, S. Knecht, J. Kongsted, U. Ryde, and T. Saue, Theoretical 57Fe Mössbauer Spectroscopy: Isomer shifts of [Fe]-Hydrogenase Intermediates.
Phys. Chem. Chem. Phys.16, 4853-4863 (2014).

25. S. Knecht, O. Legeza, and M. Reiher, Four-component density matrix renormalization group.
Communication: J. Chem. Phys.140, 041101 (2014).
arXiv:1312.0970

24. K. Aidas, C. Angeli, K. L. Bak, V. Bakken, R. Bast, L. Boman, O. Christiansen, R. Cimiraglia, S. Coriani, P. Dahle, E. K. Dalskov, U. Ekstroem, T. Enevoldsen, J. J. Eriksen, P. Ettenhuber, B. Fernandez, L. Ferrighi, H. Fliegl, L. Frediani, K. Hald, A. Halkier, C. Haettig, H. Heiberg, T. Helgaker, A. C. Hennum, H. Hettema, E. Hjertenaes, S. Hoest, I.-M. Hoeyvik, M. Francesca Iozzi, B. Jansik, H. J. Aa. Jensen, D. Jonsson, P. Joergensen, J. Kauczor, S. Kirpekar, T. Kjaergaard, W. Klopper, S. Knecht, R. Kobayashi, H. Koch, J. Kongsted, A. Krapp, K. Kristensen, A. Ligabue, O. B. Lutnaes, J. I. Melo, K. V. Mikkelsen, R. H. Myhre, C. Neiss, C. B. Nielsen, P. Norman, J. Olsen, J. M. H. Olsen, A. Osted, M. J. Packer, F. Pawlowski, Thomas B. Pedersen, P. F. Provasi, S. Reine, Z. Rinkevicius, T. A. Ruden, K. Ruud, V. Rybkin, P. Salek, C. C. M. Samson, A. Sanchez de Meras, T. Saue, S. P. A. Sauer, B. Schimmelpfennig, K. Sneskov, A. H. Steindal, K. O. Sylvester-Hvid, P. R. Taylor, A. M. Teale, E. I. Tellgren, D. P. Tew, A. J. Thorvaldsen, L. Thoegersen, O. Vahtras, M. A. Watson, D. J. D. Wilson, M. Ziolkowski and H. Aagren, The DALTON quantum chemistry program system.
WIREs Comput. Mol. Sci., 4, 269–284 (2014).

2013

23. E. D. Hedegaard, F. Heiden, S. Knecht, E. Fromager, and H. J. Aa. Jensen, Assessment of charge-transfer excitations with time-dependent, range-separated density functional theory based on long-range MP2 and multiconfigurational self-consistent field wave functions.
J. Chem. Phys.139, 184308 (2013).

22. S. Knecht, C. M. Marian, J. Kongsted, and B. Mennucci, On the photophysics of carotenoids: A multireference DFT study of peridinin.
J. Phys. Chem. B.117, 13808-13815 (2013).

21. N. Holmgaard List, C. Curutchet, S. Knecht, B. Mennucci, and J. Kongsted, Toward reliable prediction of the energy ladder in multichromophoric systems: A benchmark study on the FMO light-harvesting complex.
J. Chem. Theory Comput.9, 4928-4938 (2013).

20. C. A. Guido, S. Knecht, J. Kongsted, and B. Mennucci, Benchmarking TD-DFT for excited state geometries of organic molecules in gas-phase and in solution.
J. Chem. Theory Comput.9, 2209-2220 (2013)

19. E. Fromager, S. Knecht, and H. J. Aa. Jensen, Multiconfigurational time-dependent density-functional theory based on range separation.
J. Chem. Phys.138, 084101 (2013).

2012

18. V. Arcisauskaite, S. Knecht, S. P. A. Sauer, and L. Hemmingsen, Electric Field Gradients in Hg compounds: Molecular Orbital (MO) analysis and Comparison of Four-component and Two-component (ZORA) methods.
Phys. Chem. Chem. Phys.14, 16070-16079 (2012).

17. S. Höfener, R. Ahlrichs, S. Knecht, and L. Visscher, Relativistic and non-relativistic electronic molecular structure calculations for dimers of 4p-, 5p-, and 6p-block elements.
ChemPhysChem13, 3952-3957 (2012).

16. P. S. Bagus, E. S. Ilton, R. L. Martin, H. J. Aa. Jensen, and S. Knecht, Spin-orbit coupling in actinide cations.
Chem. Phys. Lett.546, 58-62 (2012).

15. K. R. Geethalakshmi, F. Ruiperez, S. Knecht, J. M. Ugalde, M. Morse, and I. Infante, An interpretation of the absorption and emission spectra of the gold dimer using modern theoretical tools.
Phys. Chem. Chem. Phys.14, 8732-8741 (2012).

14. L. Veis, J. Visnak, T. Fleig, S. Knecht, T. Saue, L. Visscher, and J. Pittner, Relativistic quantum chemistry on quantum computers.
Phys. Rev. A85, 030304 (2012).

13. V. Arcisauskaite, S. Knecht, S. P. A. Sauer, and L. Hemmingsen, Fully relativistic coupled cluster study of electric field gradients at Hg in 199Hg compounds.
Phys. Chem. Chem. Phys.14, 2651-2657 (2012).

2011

12. S. Knecht and T. Saue, Nuclear size effects in rotational spectra: a tale with a twist.
Chem. Phys.401,103-112 (2012).

11. J. B. Rota, S. Knecht, T. Fleig, D. Ganyushin, T. Saue, F. Neese, and H. Bolvin, Zero Field Splitting of the chalcogen diatomics using relativistic correlated wave-function methods.
J. Chem. Phys.135, 114106 (2011).

10. S. Knecht, S. Fux, R. van Meer, L. Visscher, M. Reiher, and T. Saue, Mössbauer spectroscopy for heavy elements: a relativistic benchmark study of mercury.
Theor. Chem. Acc.129, 631-650 (2011).

2010

9. A. S. P. Gomez, L. Visscher, H. Bolvin, T. Saue, S. Knecht, T. Fleig, and E. Eliav, The electronic structure of the triiodide ion from relativistic correlated calculations: A comparison of different methodologies.
J. Chem. Phys.133, 064305 (2010).

8. S. Knecht, L. K. Sørensen, H. J. Aa. Jensen, T. Fleig, and C. M. Marian, Accurate calculations of the ground state and low-lying excited states of the (Rb-Ba)+ molecular ion:a proposed system for ultracold reactive collisions.
J. Phys. B: At. Mol. Opt. Phys.43, 055101 (2010).

7. S. Knecht, H. J. Aa. Jensen, and T. Fleig, Large-scale parallel configuration interaction. II. Two- and four-component double-group general active space implementation with application to BiH.
J. Chem. Phys.132, 014108 (2010).

2009

6. L. K. Sørensen, S. Knecht, T. Fleig, and C. M. Marian, Four-component relativistic coupled cluster and configuration interaction calculations on the ground and excited states of the RbYb molecule.
J. Phys. Chem. A113, 12607-12614 (2009).

2008

5. S. Knecht, H. J. Aa. Jensen and T. Fleig, Large-scale parallel configuration interaction. I. Non-relativistic and scalar-relativistic general active space implementation with application to (Rb-Ba)+.
J. Chem. Phys., 128, 014108 (2008).

2007

4. T. Fleig, S. Knecht, and C. Hättig, Quantum-chemical investigation of the structures and electronic spectra of the nucleic acid bases at the coupled cluster CC2 level.
J. Phys. Chem. A, 111, 5482 (2007).

2006

3. M. Pernpointner, S. Knecht, and L. S. Cederbaum, Ionization spectra and electronic decay in small iodide clusters: fully relativistic results.
J. Chem. Phys., 125, 034309 (2006).

2005

2. M. Pernpointner and S. Knecht, The influence of relativistic effects on the ionization spectra of the alkali iodides.
Chem. Phys. Lett. 410, 423 (2005).

1. T. Sommerfeld and S. Knecht, Electronic interaction between valence and dipole-bound states of the cyanoacetylene anion.
E. Phys. J. D35, 207-216 (2005).

Popular Science Articles

1. S. Knecht, Trendbericht Theoretische Chemie: Relativistische Quantenchemie.
Nachrichten aus der Chemie, Nov. 2019.

Habilitationsschrift

Electronic Structure Theory for the whole Periodic Table of the Elements (download link available soon)

PhD thesis

Parallel Relativistic Multiconfiguration Methods: New Powerful Tools for Heavy-Element Electronic-Structure Studies.

Diploma thesis

Untersuchung der Ionisierungsspektren und elektronischer Zerfallsreaktionen der Alkaliiodide mittels der vierkomponentigen Propagatormethode.