Fundamental theoretical chemistry, and in particular the quantum chemical topology approaches in:
1) Understanding the nature and quantifying strength of chemical bonds and non-covalent interactions.
2) Exploring the origin of electron density (ED) and quantifying individual atoms and molecular fragments contributions to an inter-nuclear region; hence, exploring a multicentric character of classical and non-classical interactions by use of Fragment, Atom, Localized, Delocalized and Interatomic (FALDI) electron density decomposition scheme.
3) Exploring the role played by MOs and NBOs in terms of their nature and quantified contributions made to chemical bonds and non-covalent interactions using the ), MO-ED and MO-DI methods.
4) Explaining reaction pathways and mechanisms by exploring leading attractive and repulsive inter-atomic, inter-fragment and inter-molecular interactions that drive or obstract a chemical change using the REP-FAMSEC (Reaction Energy Profile–Fragment Attributed Molecular System Energy Change) method.
5) Exploring and explaining relative stability of a wide-range of molecular systems (poly-molecular systems, classical metal complexes, organometallic complexes, etc.) using the FAMSEC and p-FARMS (Preorganized-interacting Fragment Attributed Relative Molecular Stability) methods.
6) The development of tools useful for investigating the above.
Recent Journal articles
B. K. Mdhluli, W. Nxumalo and I. Cukrowski, ‘A REP-FAMSEC Method as a Tool in Explaining Reaction Mechanisms: A Nucleophilic Substitution of 2-Phenylquinoxaline as a DFT Case Study’, Molecules, 2021, 26, 1570. DOI: 10.3390/molecules26061570
T. G. Bates, J. H. de Lange and I. Cukrowski, ‘The CH×××HC interaction in biphenyl is a delocalized, molecular-wide and entirely non-classical interaction: results from FALDI analysis.’ J. Comput. Chem., 2021, DOI: 10.1002/jcc.26491
S. de Beer, I. Cukrowski, J. H. de Lange, ‘Characterization of bonding modes in metal complexes through electron density cross-sections’, J. Comput. Chem., 2020, 41, 2695–2706. DOI: 10.1002/jcc.26423.
M. P. Mitoraj, F. Sagan, D. W. Szczepanik, J. H. de Lange, A. L. Ptaszek, D. M. E. van Niekerk and I. Cukrowski, ‘Origin of Hydrocarbons Stability from Computational Perspective – A Case Study of Xylene Isomers’, ChemPhysChem, 2020, 21, 494–502. DOI: 10.1002/cphc.202000066.
J. H. de Lange, D. M. E. van Niekerk and I. Cukrowski, ‘Quantifying individual (anti)bonding molecular orbitals’ contributions to chemical bonding’, Phys. Chem. Chem. Phys., 2019, 21, 20988-20998. DOI: 10.1039/C9CP04345D
I. Cukrowski, G. Dhimba and D. L. Riley, ‘Reaction energy profile and fragment attributed molecular system energy change (FAMSEC)-based protocol designed to uncover reaction mechanism: A case study of the proline catalyzed aldol reaction’, Phys. Chem. Chem. Phys., 2019, 21, 16694-16705. DOI: 10.1039/C9CP03046H.
I Cukrowski, ‘Reliability of HF/IQA, B3LYP/IQA, and MP2/IQA data in interpreting the nature and strength of interactions”, Phys. Chem. Chem. Phys. 2019, 21, 10244-10260.
J. H. de Lange, D. M. E. van Niekerk and I. Cukrowski, “FALDI-Based Criterion for and the Origin of an Electron Density Bridge with an Associated (3,–1) Critical Point on Bader’s Molecular Graph”, J. Comput. Chem., 2018, 39, 2283-2299. DOI:10.1002/jcc.25548
J. H. de Lange and I. Cukrowski, “Exact and Exclusive Electron Localization Indices Within QTAIM Atomic Basins”, J. Comput. Chem., 2018, 39, 1517–1530. DOI: 10.1002/jcc.25223
J. H. de Lange, D. M. E. van Niekerk and I. Cukrowski, “FALDI-based decomposition of an atomic interaction line leads to 3D representation of the multicentre nature of interactions”, J. Comput. Chem., 2018, 39, 973–985. DOI: 10.1002/jcc.25175
R. Fraser, P, H. van Rooyen, J. de Lange, I. Cukrowski and M. Landman, “Synthesis, structure and DFT study of asymmetrical NHC complexes of cymantrene derivatives and their application in the dehydrogenative dimerization reaction of thiols”, J. Organomet. Chem., 2017, 840, 11-22. DOI: 10.1016/j.jorganchem.2017.03.047
J.H. de Lange and I. Cukrowski, “Toward Deformation Densities for Intramolecular Interactions without Radical Reference States Using the Fragment, Atom, Localized, Delocalized, and Interatomic (FALDI) Charge Density Decomposition Scheme”, J. Comput. Chem. 2017, 38, 981–997. DOI: 10.1002/jcc.24772
I. Cukrowski and P.M. Polestshuk, “Reliability of Interacting Quantum Atoms (IQA) Data Computed from Post-HF Densities: Impact of Approximation Used”, Phys. Chem. Chem. Phys. 2017, 19, 16375‑16386. DOI: 10.1039/c7cp02216f
I. Cukrowski, D.M.E. van Niekerk, J. H. de Lange, “Exploring fundamental differences between red- and blue-shifted intramolecular hydrogen bonds using FAMSEC, FALDI, IQA and QTAIM, Struct. Chem. 2017, 28, 1429–1444. DOI 10.1007/s11224-017-0956-5
I. Cukrowski, J.H. de Lange, F. Groenewald and H.G. Raubenheimer, “Gold(I) Hydrides as Proton Acceptors in Dihydrogen Bond Formation”, ChemPhysChem, 2017, 18, 2288–2294. DOI : 10.1002/cphc.201700383
D.M.S. Buyens, P. Mangondo, I. Cukrowski and L.A. Pilcher, “Solvent-directed Regioselective Benzylation of Adenine: Characterization of N9-benzyladenine and N3-benzyladenine.” J. Heterocyclic Chem. 2017, 54, 2946–2950. DOI 10.1002/jhet.2894
F.P. Malan, E. Singleton, B.W. Bulling, I. Cukrowski, P.H. van Rooyen, and M. Landman, “CpNiBr(NHC) complexes as pre-catalysts in the chemoselective anaerobic oxidation of secondary aryl alcohols: Experimental and DFT studies”, Molecular Catalysis 2017, 432, 47–56. 10.1016/j.mcat.2016.12.023
P. Mangondo and I. Cukrowski, “On the origin of the relative stability of ZnIINTA and ZnIINTPA metal complexes. An insight from the IQA, IQF, and p-FARMS methods”, Int. J. Quantum Chem., 2017, 117:e25321 (17 pages). DOI: 10.1002/qua.25321.
C. Billing and I. Cukrowski, ‘Application of Protocols Devised to Study Bi(III) Complex Formation by Voltammetry: The Bi(III)−Picolinic Acid System’, J. Phys. Chem. B, 2016, 120, 12972−12980. DOI: 10.1021/acs.jpcb.6b10522
I. Cukrowski, F. Sagan and M. P. Mitoraj, “On the Stability of Cis- and Trans-2-Butene Isomers. An Insight Based on the FAMSEC, IQA, and ETS-NOCV Schemes”, J. Comput. Chem., 2016, 37, 2783–2798. DOI: 10.1002/jcc.24504
A.S. Adeyinka, B.W. Bulling and I. Cukrowski, “Competition Reaction-Based Prediction of Polyamines’ Stepwise Protonation Constants: a Case Study Involving 1,4,7,10-tetrazadecane (2,2,2-tet)”, Theor. Chem. Acc. 2016, 135:139,1-17. DOI 10.1007/s00214-016-1898-5
C. Billing and I. Cukrowski, “Measurements and Modelling to Determine the Reduction Potential of Uncomplexed Bi(III) in Nitrate Solutions for Application in Bi(III)-Ligand Equilibria Studies by Voltammetry”, J. Phys. Chem. B, 2016, 120, 4268−4278. DOI: 10.1021/acs.jpcb.6b00670
I. Cukrowski and P. Mangondo, “Interacting Quantum Fragments-Rooted Preorganized-Interacting Fragments Attributed Relative Molecular Stability of the BeII Complexes of Nitrilotriacetic Acid and Nitrilotri-3-propionic Acid”, J. Comput. Chem., 2016, 37, 1373–1387. DOI: 10.1002/jcc.24346
I. Cukrowski, “IQA-embedded fragment attributed molecular system energy change in exploring intramolecular interactions”, Comput. Theor. Chem., 2015, 1066, 60–76. DOI: 10.1016/j.comptc.2015.04.018
A.S. Adeyinka and I. Cukrowski, “Structural-topological preferences and protonation sequence of aliphatic polyamines: a theoretical case study of tetramine trien”, J. Mol. Model., 2015, 21:162, 1-18. DOI 10.1007/s00894-015-2709-y
C. Billing and I. Cukrowski, “A novel approach to monitoring of the diffusion junction potential in speciation studies by polarography under very acidic conditions. Part II: The quasi-reversible Cu(II)-picolinic acid system.”, Electroanalysis, 2015, 27, 494–502. DOI: 10.1002/elan.201400466
I. Cukrowski, J.H. de Lange, A.S. Adeyinka, P. Mangondo, “Evaluating common QTAIM and NCI interpretations of the electron density concentration through IQA interaction energies and 1D cross-sections of the electron and deformation density distributions.”, Comput. Theoret. Chem., 2015, 1053, 60–76. 10.1016/j.comptc.2014.10.005