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A pplications of ETS-NOCV method in description of various t ypes of chemical bonds. Mariusz P. Mitoraj. Jagiellonian University Cracow, Poland Department of Theoretical Chemistry. ADF webinar, Kraków-rest-of-the-world, 28th Feb., 2014.
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Applications of ETS-NOCVmethodin description of various types of chemicalbonds MariuszP. Mitoraj Jagiellonian University Cracow, Poland Department of Theoretical Chemistry ADF webinar, Kraków-rest-of-the-world, 28th Feb., 2014
Examples of theoretical quantities for visualization of chemical bond ADF webinar, Kraków-restoftheworld, 28th Feb., 2014
Formation of chemical bond in H2 – based picture 1. Start from promolecular state (atom/fragments) H H H2 H=1s2 H=1s2 H H Deformation density (Differential density) (1) qualitative data by inspection of the sign of : negative (outflow), positive (inflow) of density due to bond formation ADF webinar, Kraków-restoftheworld, 28th Feb., 2014
NOCV’s ( ) diagonalize the deformation density matrix: where P=P-P0 , density matrix of the combined molecule, P0- density matrix of the considered molecular fragments. NOCV’s also decompose the deformation density : useful qualitative data by inspection of the sign of : negative (outflow), positive (inflow) of density NOCV’s are in pairs: Radoń, M. Theor Chem Account 2008, 120,337. The Natural Orbitals for Chemical Valence (NOCV) Mitoraj, M.; Michalak, A. Organometallics 2007, 26(26); 6576., Michalak, A.; Mitoraj, M.; Ziegler, T. J. Phys. Chem. A. 2008, 112 (9), 1933, Mitoraj, M.; Michalak, A. J. Mol. Model., 2008, 14, 681, Mitoraj, M.; Zhu, H.; Michalak, A.; Ziegler, T. 2008, International Journal of Quantum Chemistry, DOI: 10.1002/qua.21910., Mitoraj, M.; Michalak, A. J. Mol. Model.2008, 14, 681.
donation back donation back donation The contours of the deformation density () and the contributions from the pairs of complementary orbitals for the heme/CO system q = 0.74 q = 1.04
-De=Etotal= Edist + Eelstat + EPauli + Eorb ETS: NOCV: ETS-NOCV: Energetic estimation of k A combination of ETS and NOCV - (ETS-NOCV) electronic factor Mariusz P. Mitoraj, Artur Michalak and Tom Ziegler „A combined charge and energy decom- Position scheme for bond analysis” J. Chem. Theory Comput., 2009, 5 (4), pp 962–975.
(CO)5Cr=CH2 donation :CN- > PH3>NH3>C2H4 >CS>CO > N2>NO+ :NO+>CS>CO > N2>C2H4>PH3>CN-> NH3 for Ni(NH3)3 X complexes: back donation Donor/acceptor properties of ligands Dativebonds – systems with symmetry Mitoraj Mariusz, Michalak A (2007) „ Donor-Acceptor Properties of Ligands from the Natural Orbitals for Chemical Valence” Organometallics, 26, 6576-6580
Dative Bond NH3BH3 - Calculations • Defineclosedshellfragments, NH3 and BH3 • Run SP calculations to get the fragment MO’s • Run SP ETS-NOCV calculations for wholemolecule in the basis • of previouslycalculated fragment MO’s
Dative Bond NH3BH3 - Calculations M.Mitoraj J. Phys. Chem. A, 2011, 115 (51), pp 14708–14716
Crystal of AmmoniaBorane, NH3BH3 M.Mitoraj J. Phys. Chem. A, 2011, 115 (51), pp 14708–14716
Adenine-Thymine Inter-Molecular-Hydrogen Bonds Eorb=-22.0 Os*(H-N) Ns*(H-N) O-H Rafał Kurczab, Mariusz P. Mitoraj, Artur Michalak and Tom Ziegler J. Phys. Chem. A,2010, 114, 8581. H-N covalency!
Hydrogen Bond A-TCalculations • Defineclosedshellfragments, Adenine and Thymine • Run SP calculations to get the fragment MO’s • Run SP ETS-NOCV calculations for wholemolecule in the basis • of previouslycalculated fragment MO’s ADF webinar, Kraków-restoftheworld, 28th Feb., 2014
H3CCCCH3 GeH2=GeH2 CH2=CH2 CH3-CH3 Covalent bonds
1[-65.5 kcal/mol] [-84.3 kcal/mol] 2[-65.5 kcal/mol] [-1.3 kcal/mol] Quadruple bond; Re2Cl82-
Typical-Multiple bonds-TM Cr2, formally sixtuple bond, bCr2-Nal = 6.01 Etotal=-31.3kcal/mol Eorb=-242.7 Esteric=211.4 Eorb=-242.7 kcal/mol J. Chem. Theory Comput., 2009, 5 (4), pp 962–975.
EthaneBuilt from twomethylradicals 1. Define CH3 regions (uneven number of electrons); 2. Run SP RESTRICTED ! Calculations for CH3 fragments to get the fragment MO’s; (1/2 + 1/2 electrons for SOMO of CH3) 3. Use fragoccupations keyword in order to keep the right occupations for each CH3 fragoccupations f1 A 5 // 4 subend f2 A 4 // 5 subend End 4. Run SP ETS-NOCV calculations for whole molecule in the basis of previously calculated fragment MO’s -alpha-and beta-NOCV’s
Typical-Multiplebonds-TM Cr2, sextuple bond, bCr2-Nal = 6.01 Etotal=-31.3kcal/mol Eorb=-242.7 Esteric=211.4 Eorb=-242.7 kcal/mol J. Chem. Theory Comput., 2009, 5 (4), pp 962–975.
Cr2Built from two Cr+Cr 1. Define Cr regions (unevennumber of electrons); 2. Run SP RESTRICTED ! Calculations for Cr fragments usingOCCUPATIONkeyword (A 18 1 1 1 1 1 1); Should be like Cr but itisCr 6* (1/2 + 1/2) so we must: 3. Usefragoccupationskeyword in order to keep the rightoccupations for each Cr. fragoccupations Region_1 A 15//9 subend Region_2 A 9//15 subend End 4. Run SP ETS-NOCV calculations for wholemolecule in the basis of previouslycalculated fragment MO’s Cr Cr
Better Fragment MO’s from unrestriced run: advanced ’manual’ usage ADF uses in principle only ‚rectricted’ fragments, however, one might cheat him 1. Run open shell calculations for a given fragment; 2. Save tape21 ascii (dmpkf) copy the final MO’s (from the section Eig-CoreSFO_A, MO’s expressed in SFO); 3. Run fragment calculations by setting SCF=0 wrong MO’s save tape21asciifind Eig-CoreSFO_A section, then: 4. Take MO’s and occupations, energies, from step 2 and paste them to Tape21 from step 3…..it gives you right fragment MO’s Transform asciibinary(udmpkf); 5. Rerun final ETSNOCV calculations (do not recalculate the fragments!)
Ni-diimine cationic Brookhart model catalyst Agostic intramolecular RH---Metal interaction Cb-H polarization Ca-Cb Ni-Ca Mariusz P. Mitoraj, Artur Michalak and Tom Ziegler „On the Nature of the Agostic Bond between Metal Centers and -Hydrogen Atoms in Alkyl Complexes. An Analysis Based on the Extended Transition State Method and the Natural Orbitals for Chemical Valence Scheme (ETS-NOCV)” Organometallics, 2009, 28 (13), pp 3727
Halogen Bonding CF3I---NH3 from ETS-NOCV perspective Charge outflow, increase positive charge ETSNOCV(red-outflow,blue-inflow) -8.3 kcal/mol N-I covalency Ns*(C-F) charge accumulation, increase s-character (pointed out by prof. Grabowski) Grabowski S. Chem. Rev., 2011, 111 (4), pp 2597–2625
Halogen Bonding CF3I---NH3 from ETS-NOCV perspective Domination of the electrostatic factor is due to the presense of σ-hole on iodine atom: I F F F (Politzer P, Lane P, Concha MC, Ma Y, Murray J (2007) JMolModel, 13, 305, „An Overview of Halogen Bonding”
Halogen Bonding CF3I---NH3 from ETS-NOCV perspective Prof. Politzer, „Program & Book of Abstracts”, MIB 2011, „….The weakness of this interpretation (electrostatic) is that it is simple and straightforward, and therefore is viewed by some with suspicion. s(C-F) bond s-hole I F F Electrostatic potential picture F Charge Anisotropy ETS-NOCV picture
Can ETS-NOCV discriminate between halogen and hydrogen bonding within the same molecule? Anion receptor based on urea, which involve hydrogen and halogen Bonding at the same time|: Chudzinski, et all, JACS, 2011, 133, 10559
Can ETS-NOCV discriminate between halogen and hydrogen bonding within the same molecule? -22.3 kcal/mol -6.3 kcal/mol Yes: ETS-NOCV can separate halogen and hydrogen connections
Cl- / rest • Defineclosedshellfragments, Cl minus + rest of the complex • Run SP calculations to get the fragment MO’s • Run SP ETS-NOCV calculations for wholemolecule in the basis • of previouslycalculated fragment MO’s ADF webinar, Kraków-restoftheworld, 28th Feb., 2014
Thank You very much for Your Attention! ADF webinar, Kraków-restoftheworld, 28th Feb., 2014