What is the nature of bonding in [Fe(CO)3(NO)] and [Fe(CO)4]2−?


To shed new light on the electronic structure of [Fe(CO)3(NO)]¯ complex ion, DFT-based analysis of the nature of chemical bonding has been performed. For this purpose, the extended transition state energy decomposition analysis alongside the natural orbitals for chemical valence has been used and results are compared to the nature and the strength of the interactions in isoelectronic [Fe(CO)4]2− complex ion. Based on orbital contribution to the interaction energy and charge flow between the fragments, the ground state can be best described as an open-shell singlet with zero formal oxidation state on iron and negative charge on the nitrosyl ligand. It is in agreement with the different nature of interactions when NO+ and CO ligands are bonded to Fe(−II).

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  1. 1.

    Chan WTK, Wong WT (2013) A brief introduction to transition metals in unusual oxidation states. Polyhedron 52:43–61. https://doi.org/10.1016/j.poly.2012.09.004

    CAS  Article  Google Scholar 

  2. 2.

    Ellis JE (2006) Adventures with substances containing metals in negative oxidation states. Inorg Chem 45:3167–3186. https://doi.org/10.1021/ic052110i

    CAS  Article  PubMed  Google Scholar 

  3. 3.

    Allan M, Lacko M, Papp P, Matejčík Š, Zlatar M, Fabrikant II, Kočišek J, Fedor J (2018) Dissociative electron attachment and electronic excitation in Fe(CO)5. Phys Chem Chem Phys 20:11692–11701. https://doi.org/10.1039/C8CP01387J

    CAS  Article  PubMed  Google Scholar 

  4. 4.

    Ellis JE (2003) Metal carbonyl anions: from [Fe(CO)4]2- to [Hf(CO)6]2- and beyond. Organometallics 22:3322–3338. https://doi.org/10.1021/om030105l

    CAS  Article  Google Scholar 

  5. 5.

    Plietker B, Dieskau A (2009) The reincarnation of the Hieber Anion [Fe(CO)3(NO)] − : a new venue in nucleophilic metal catalysis. Eur J Org Chem 2009:775–787. https://doi.org/10.1002/ejoc.200800893

    CAS  Article  Google Scholar 

  6. 6.

    Klein JEMN, Miehlich B, Holzwarth MS, Bauer M, Milek M, Khusniyarov MM, Knizia G, Werner H-J, Plietker B (2014) The electronic ground state of [Fe(CO)3(NO)]: a spectroscopic and theoretical study. Angew Chemie Int Ed 53:1790–1794. https://doi.org/10.1002/anie.201309767

    CAS  Article  Google Scholar 

  7. 7.

    Burkhardt L, Vukadinovic Y, Nowakowski M, Kalinko A, Rudolph J, Carlsson P-A, Jacob CR, Bauer M (2020) Electronic Structure of the Hieber Anion [Fe(CO)3(NO)]: revisited by X-ray emission and absorption spectroscopy. Inorg Chem 59:3551–3561. https://doi.org/10.1021/acs.inorgchem.9b02092

    CAS  Article  PubMed  Google Scholar 

  8. 8.

    Klein JEMN, Knizia G, Miehlich B, Kästner J, Plietker B (2014) Fe or Fe − NO catalysis? A quantum chemical investigation of the [Fe(CO)3(NO)]: catalyzed Cloke–Wilson rearrangement. Chem A Eur J 20:7254–7257. https://doi.org/10.1002/chem.201402716

    CAS  Article  Google Scholar 

  9. 9.

    Weisser F, Klein JEMN, Sarkar B, Plietker B (2014) Spectroelectrochemical investigation of Bu4N[Fe(CO)3(NO)]: identification of a reversible EC-mechanism. Dalt Trans 43:883–887. https://doi.org/10.1039/C3DT51998H

    CAS  Article  Google Scholar 

  10. 10.

    Klein J (2011) The Hieber Anion [Fe(CO)3(NO)]. Synlett 2011:2757–2758. https://doi.org/10.1055/s-0031-1289559

    CAS  Article  Google Scholar 

  11. 11.

    Teller RG, Finke RG, Collman JP, Chin HB, Bau R (1977) Dependence of the tetracarbonylferrate(2-) geometry on counterion: crystal structures of dipotassium tetracarbonylferrate and bis(sodium crypt) tetracarbonylferrate [crypt = N(CH2CH2OCH2CH2OCH2CH2)3 N]. J Am Chem Soc 99:1104–1111. https://doi.org/10.1021/ja00446a022

    CAS  Article  Google Scholar 

  12. 12.

    Collman JP (1975) Disodium tetracarbonylferrate, a transition metal analog of a Grignard reagent. Acc Chem Res 8:342–347. https://doi.org/10.1021/ar50094a004

    CAS  Article  Google Scholar 

  13. 13.

    Cramer CJ, Truhlar DG (2009) Density functional theory for transition metals and transition metal chemistry. Phys Chem Chem Phys 11:10757. https://doi.org/10.1039/b907148b

    CAS  Article  PubMed  Google Scholar 

  14. 14.

    Zlatar M, Gruden M (2020) Introduction to ligand field theory and computational chemistry. In: Crichton RR, Louro RO (eds) Practical approaches to biological inorganic chemistry, 2nd edn. Elsevier, Amsterdam, pp 17–67

    Google Scholar 

  15. 15.

    Singh SK, Eng J, Atanasov M, Neese F (2017) Covalency and chemical bonding in transition metal complexes: an ab initio based ligand field perspective. Coord Chem Rev 344:2–25. https://doi.org/10.1016/j.ccr.2017.03.018

    CAS  Article  Google Scholar 

  16. 16.

    Reiher M (2009) A theoretical challenge: transition-metal compounds. Chimia (Aarau) 63:140–145. https://doi.org/10.2533/chimia.2009.140

    CAS  Article  Google Scholar 

  17. 17.

    Jørgensen CK (1966) Differences between the four halide ligands, and discussion remarks on trigonal-bipyramidal complexes, on oxidation states, and on diagonal elements of one-electron energy. Coord Chem Rev 1:164–178. https://doi.org/10.1016/S0010-8545(00)80170-8

    Article  Google Scholar 

  18. 18.

    Enemark JH, Feltham RD (1974) Principles of structure, bonding, and reactivity for metal nitrosyl complexes. Coord Chem Rev 13:339–406. https://doi.org/10.1016/S0010-8545(00)80259-3

    CAS  Article  Google Scholar 

  19. 19.

    Kaim W, Das A, Fiedler J, Záliš S, Sarkar B (2020) NO and NO2 as non-innocent ligands: a comparison. Coord Chem Rev 404:213114. https://doi.org/10.1016/j.ccr.2019.213114

    CAS  Article  Google Scholar 

  20. 20.

    Ye S, Neese F (2010) The unusual electronic structure of dinitrosyl iron complexes. J Am Chem Soc 132:3646–3647. https://doi.org/10.1021/ja9091616

    CAS  Article  PubMed  Google Scholar 

  21. 21.

    Monsch G, Klüfers P (2019) [Fe(H2O)5(NO)]2+, the “Brown-Ring” chromophore. Angew Chemie Int Ed 58:8566–8571. https://doi.org/10.1002/anie.201902374

    CAS  Article  Google Scholar 

  22. 22.

    Boulet P, Buchs M, Chermette H, Daul C, Gilardoni F, Rogemond F, Schläpfer CW, Weber J (2001) DFT investigation of metal complexes containing a Nitrosyl Ligand. 1. Ground state and metastable states. J Phys Chem A 105:8991–8998. https://doi.org/10.1021/jp010988z

    CAS  Article  Google Scholar 

  23. 23.

    Boulet P, Buchs M, Chermette H, Daul C, Furet E, Gilardoni F, Rogemond F, Schläpfer CW, Weber J (2001) DFT investigation of metal complexes containing a nitrosyl ligand. 2. Excited States. J Phys Chem A 105:8999–9003. https://doi.org/10.1021/jp010989r

    CAS  Article  Google Scholar 

  24. 24.

    Noodleman L (1981) Valence bond description of antiferromagnetic coupling in transition metal dimers. J Chem Phys 74:5737–5743. https://doi.org/10.1063/1.440939

    CAS  Article  Google Scholar 

  25. 25.

    Noodleman L, Davidson ER (1986) Ligand spin polarization and antiferromagnetic coupling in transition metal dimers. Chem Phys 109:131–143. https://doi.org/10.1016/0301-0104(86)80192-6

    Article  Google Scholar 

  26. 26.

    Neese F (2009) Prediction of molecular properties and molecular spectroscopy with density functional theory: from fundamental theory to exchange-coupling. Coord Chem Rev 253:526–563. https://doi.org/10.1016/j.ccr.2008.05.014

    CAS  Article  Google Scholar 

  27. 27.

    Zhang Y, Yang W (1998) A challenge for density functionals: self-interaction error increases for systems with a noninteger number of electrons. J Chem Phys 109:2604–2608. https://doi.org/10.1063/1.476859

    CAS  Article  Google Scholar 

  28. 28.

    Parthey M, Kaupp M (2014) Quantum-chemical insights into mixed-valence systems: within and beyond the Robin–Day scheme. Chem Soc Rev 43:5067–5088. https://doi.org/10.1039/C3CS60481K

    CAS  Article  PubMed  Google Scholar 

  29. 29.

    Bally T, Sastry GN (1997) Incorrect dissociation behavior of radical ions in density functional calculations. J Phys Chem A 101:7923–7925. https://doi.org/10.1021/jp972378y

    CAS  Article  Google Scholar 

  30. 30.

    Chermette H, Ciofini I, Mariotti F, Daul C (2001) Correct dissociation behavior of radical ions such as H2+ in density functional calculations. J Chem Phys 114:1447–1453. https://doi.org/10.1063/1.1332989

    CAS  Article  Google Scholar 

  31. 31.

    Dreuw A, Head-Gordon M (2004) Failure of time-dependent density functional theory for long-range charge-transfer excited states: the zincbacteriochlorin − bacteriochlorin and bacteriochlorophyll − spheroidene complexes. J Am Chem Soc 126:4007–4016. https://doi.org/10.1021/ja039556n

    CAS  Article  PubMed  Google Scholar 

  32. 32.

    Gerber IC, Ángyán JG (2005) Hybrid functional with separated range. Chem Phys Lett 415:100–105. https://doi.org/10.1016/j.cplett.2005.08.060

    CAS  Article  Google Scholar 

  33. 33.

    Vydrov OA, Scuseria GE (2006) Assessment of a long-range corrected hybrid functional. J Chem Phys 125:234109. https://doi.org/10.1063/1.2409292

    CAS  Article  PubMed  Google Scholar 

  34. 34.

    Renz M, Theilacker K, Lambert C, Kaupp M (2009) A reliable quantum-chemical protocol for the characterization of organic mixed-valence compounds. J Am Chem Soc 131:16292–16302. https://doi.org/10.1021/ja9070859

    CAS  Article  PubMed  Google Scholar 

  35. 35.

    Kaduk B, Kowalczyk T, Van Voorhis T (2012) Constrained density functional theory. Chem Rev 112:321–370. https://doi.org/10.1021/cr200148b

    CAS  Article  PubMed  Google Scholar 

  36. 36.

    Daul C (1994) Density functional theory applied to the excited states of coordination compounds. Int J Quantum Chem 52:867–877. https://doi.org/10.1002/qua.560520414

    CAS  Article  Google Scholar 

  37. 37.

    Ziegler T, Rauk A (1977) On the calculation of bonding energies by the Hartree Fock Slater method. Theor Chim Acta 46:1–10. https://doi.org/10.1007/BF02401406

    CAS  Article  Google Scholar 

  38. 38.

    Ziegler T, Rauk A (1979) A theoretical study of the ethylene-metal bond in complexes between copper(1 +), silver(1 +), gold(1 +), platinum(0) or platinum(2 +) and ethylene, based on the Hartree–Fock–Slater transition-state method. Inorg Chem 18:1558–1565. https://doi.org/10.1021/ic50196a034

    CAS  Article  Google Scholar 

  39. 39.

    Bickelhaupt FM, Baerends EJ (2000) Kohn-Sham density functional theory: predicting and understanding chemistry. In: Lipkowitz KB, Boyd DB (eds) Reviews in computational chemistry. Wiley-VCH Verlag, London, pp 1–86

    Google Scholar 

  40. 40.

    Nalewajski RF, Mrozek J, Mazur G (1996) Quantum chemical valence indices from the one-determinantal difference approach. Can J Chem 74:1121–1130. https://doi.org/10.1139/v96-126

    CAS  Article  Google Scholar 

  41. 41.

    Mitoraj MP, Michalak A, Ziegler T (2009) A combined charge and energy decomposition scheme for bond analysis. J Chem Theory Comput 5:962–975. https://doi.org/10.1021/ct800503d

    CAS  Article  PubMed  Google Scholar 

  42. 42.

    Vujović M, Zlatar M, Milčić M, Gruden M (2017) in/out Isomerism of cyclophanes: a theoretical account of 2,6,15-trithia-[3 4,10][7]metacyclophane and [3 4,10][7]metacyclophane as well as their halogen substituted analogues. Phys Chem Chem Phys 19:9500–9508. https://doi.org/10.1039/C7CP00557A

    CAS  Article  PubMed  Google Scholar 

  43. 43.

    Zlatar M, Allan M, Fedor J (2016) Excited states of Pt(PF3)4 and their role in focused electron beam nanofabrication. J Phys Chem C 120:10667–10674. https://doi.org/10.1021/acs.jpcc.6b02660

    CAS  Article  Google Scholar 

  44. 44.

    Vermeeren P, van der Lubbe SCC, Fonseca Guerra C, Bickelhaupt FM, Hamlin TA (2020) Understanding chemical reactivity using the activation strain model. Nat Protoc 15:649–667. https://doi.org/10.1038/s41596-019-0265-0

    CAS  Article  PubMed  Google Scholar 

  45. 45.

    Wu X, Zhao L, Jin J, Pan S, Li W, Jin X, Wang G, Zhou M, Frenking G (2018) Observation of alkaline earth complexes M(CO)8 (M = Ca, Sr, or Ba) that mimic transition metals. Science 361:912–916. https://doi.org/10.1126/science.aau0839

    CAS  Article  PubMed  Google Scholar 

  46. 46.

    Baerends EJ, Ziegler T, Atkins AJ et al (2019) ADF2019, SCM, theoretical chemistry. Vrije Universiteit, Amsterdam. http://www.scm.com

    Google Scholar 

  47. 47.

    te Velde G, Bickelhaupt FM, Baerends EJ, Fonseca Guerra C, van Gisbergen SJA, Snijders JG, Ziegler T (2001) Chemistry with ADF. J Comput Chem 22:931–967. https://doi.org/10.1002/jcc.1056

    Article  Google Scholar 

  48. 48.

    Guerra CF, Snijders JG, te Velde G, Baerends EJ (1998) Towards an order-N DFT method. Theor Chem Acc 99:391–403

    CAS  Google Scholar 

  49. 49.

    van Lenthe E, Baerends EJ, Snijders JG (1993) Relativistic regular two-component Hamiltonians. J Chem Phys 99:4597–4610. https://doi.org/10.1063/1.466059

    Article  Google Scholar 

  50. 50.

    Clarkson LM, Clegg W, Hockless DCR, Norman NC (1992) Structure of a thallium(I) transition-metal carbonyl salt Tl[Fe(CO)3(NO)]. Acta Crystallogr Sect C: Cryst Struct Commun 48:236–239. https://doi.org/10.1107/s0108270191010405

    Article  Google Scholar 

  51. 51.

    Seth M, Ziegler T (2012) Range-separated exchange functionals with Slater-type functions. J Chem Theory Comput 8:901–907. https://doi.org/10.1021/ct300006h

    CAS  Article  PubMed  Google Scholar 

  52. 52.

    Akinaga Y, Ten-no S (2008) Range-separation by the Yukawa potential in long-range corrected density functional theory with Gaussian-type basis functions. Chem Phys Lett 462:348–351. https://doi.org/10.1016/j.cplett.2008.07.103

    CAS  Article  Google Scholar 

  53. 53.

    Yanai T, Tew DP, Handy NC (2004) A new hybrid exchange-correlation functional using the Coulomb-attenuating method (CAM-B3LYP). Chem Phys Lett 393:51–57. https://doi.org/10.1016/j.cplett.2004.06.011

    CAS  Article  Google Scholar 

  54. 54.

    Becke AD (1988) Density-functional exchange-energy approximation with correct asymptotic behavior. Phys Rev A 38:3098–3100. https://doi.org/10.1103/PhysRevA.38.3098

    CAS  Article  Google Scholar 

  55. 55.

    Perdew JP (1986) Density-functional approximation for the correlation energy of the inhomogeneous electron gas. Phys Rev B 33:8822–8824. https://doi.org/10.1103/PhysRevB.33.8822

    CAS  Article  Google Scholar 

  56. 56.

    Perdew JP (1986) Erratum: Density-functional approximation for the correlation energy of the inhomogeneous electron gas. Phys Rev B 34:7406. https://doi.org/10.1103/PhysRevB.34.7406

    CAS  Article  Google Scholar 

  57. 57.

    Caldeweyher E, Ehlert S, Hansen A, Neugebauer H, Spicher S, Bannwarth C, Grimme S (2019) A generally applicable atomic-charge dependent London dispersion correction. J Chem Phys 150(15):154122

    Article  Google Scholar 

  58. 58.

    Swart M, Ehlers AW, Lammertsma K (2004) Performance of the OPBE exchange-correlation functional. Mol Phys 102:2467–2474. https://doi.org/10.1080/0026897042000275017

    CAS  Article  Google Scholar 

  59. 59.

    Zhao Y, Truhlar DG (2006) A new local density functional for main-group thermochemistry, transition metal bonding, thermochemical kinetics, and noncovalent interactions. J Chem Phys 125:194101. https://doi.org/10.1063/1.2370993

    CAS  Article  PubMed  Google Scholar 

  60. 60.

    Zhao Y, Truhlar DG (2008) The M06 suite of density functionals for main group thermochemistry, thermochemical kinetics, noncovalent interactions, excited states, and transition elements: two new functionals and systematic testing of four M06-class functionals and 12 other function. Theor Chem Acc 120:215–241. https://doi.org/10.1007/s00214-007-0310-x

    CAS  Article  Google Scholar 

  61. 61.

    Tao J, Perdew J, Staroverov V, Scuseria G (2003) Climbing the density functional ladder: nonempirical meta-generalized gradient approximation designed for molecules and solids. Phys Rev Lett 91:146401. https://doi.org/10.1103/PhysRevLett.91.146401

    CAS  Article  PubMed  Google Scholar 

  62. 62.

    Staroverov VN, Scuseria GE, Tao J, Perdew JP (2003) Comparative assessment of a new nonempirical density functional: Molecules and hydrogen-bonded complexes. J Chem Phys 119:12129. https://doi.org/10.1063/1.1626543

    CAS  Article  Google Scholar 

  63. 63.

    Sun J, Ruzsinszky A, Perdew J (2015) Strongly constrained and appropriately normed semilocal density functional. Phys Rev Lett 115:036402. https://doi.org/10.1103/PhysRevLett.115.036402

    CAS  Article  PubMed  Google Scholar 

  64. 64.

    Reiher M, Salomon O, Artur Hess B (2001) Reparameterization of hybrid functionals based on energy differences of states of different multiplicity. Theor Chem Acc 107:48–55. https://doi.org/10.1007/s00214-001-0300-3

    CAS  Article  Google Scholar 

  65. 65.

    Stephens PJ, Devlin FJ, Chabalowski CF, Frisch MJ (1994) Ab Initio calculation of vibrational absorption and circular dichroism spectra using density functional force fields. J Phys Chem 98:11623–11627. https://doi.org/10.1021/j100096a001

    CAS  Article  Google Scholar 

  66. 66.

    Hirshfeld FL (1977) Bonded-atom fragments for describing molecular charge densities. Theor Chim Acta 44:129–138. https://doi.org/10.1007/BF00549096

    CAS  Article  Google Scholar 

  67. 67.

    Sherrill CD, Lee MS, Head-Gordon M (1999) On the performance of density functional theory for symmetry-breaking problems. Chem Phys Lett 302:425–430. https://doi.org/10.1016/S0009-2614(99)00206-7

    CAS  Article  Google Scholar 

  68. 68.

    Scharf LT, Andrada DM, Frenking G, Gessner VH (2017) The bonding situation in metalated ylides. Chem - A Eur J 23:4422–4434. https://doi.org/10.1002/chem.201605997

    CAS  Article  Google Scholar 

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This work is supported by the Ministry of Education, Science, and Technological Development of the Republic of Serbia (Grants Nos. 451-03-68/2020-14/200168 and 451-03-68/2020-14/200026).

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Gruden, M., Zlatar, M. What is the nature of bonding in [Fe(CO)3(NO)] and [Fe(CO)4]2−?. Theor Chem Acc 139, 126 (2020). https://doi.org/10.1007/s00214-020-02639-3

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  • Chemical bonding
  • Energy decomposition analysis
  • DFT
  • Oxidation states
  • Iron complexes