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

in preparation

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


59. S. Knecht, M. Repisky, H. J. Aa. Jensen, and T. Saue. Exact two-component Hamiltonians for relativistic quantum chemistry: Two-electron picture-change corrections made simple.
submitted for publication in J. Chem. Phys, 08.04.2022.
arXiv: 2204.03977

58. C. E. Hoyer H. Hu, L. Lu, S. Knecht, and X. Li. Relativistic Kramers-Unrestricted Exact-Two-Component Density Matrix Renormalization Group.
submitted for publication in J. Phys. Chem. A, 29.03.2022.

under revision

accepted/in press





57. L. Freitag, A. Baiardi, S. Knecht, and L. Gonzalez. A Simplified State Interaction for Matrix Product State Wave Functions.
J. Chem. Theory Comput. 17, 7477–7485 (2021).
ChemRxiv: chemrxiv-2021-brv78

56. D. Wehrli, M. Génévriez, S. Knecht, M. Reiher, and F. Merkt. Charge-transfer–induced predissociation in Rydberg states of molecular cations: MgAr+.
J. Phys. Chem. A,  125, 6681–6696 (2021).


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


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).


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


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).

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).

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).

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).

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


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).

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).


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).

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).


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).

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).


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).


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).


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).


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).


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).


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).


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).


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).


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.


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.