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The Hydrogen Bond

The Hydrogen Bond. Jan Lundell Department of Chemistry, University of Jyväskylä. The Hydrogen Bond. Adenine. Thymine. Guanine. Cytosine. The Hydrogen Bond. Peter Agre (Nobel Prize, 2003): The purest form of hydrogen bond there is…. The Hydrogen Bond.

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The Hydrogen Bond

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  1. The Hydrogen Bond Jan LundellDepartment of Chemistry, University of Jyväskylä

  2. The Hydrogen Bond

  3. Adenine Thymine Guanine Cytosine The Hydrogen Bond Peter Agre (Nobel Prize, 2003): The purest form of hydrogen bond there is…

  4. The Hydrogen Bond • ”The hydrogen nucleus held by two octets constitutes a weak bond” W.M.Latimer and W.H.Rodebush, JACS 42, 1920, 1419 • ”Under certain conditions an atom of hydrogen is attracted by rather strong forces to two atoms instead of only one, so that it may be considered to be acting as a bond between them. This is called a hydrogen bond.” L. Pauling, Nature of Chemical Bond, 1939

  5. The Hydrogen Bond HCOOH in the gasphase – IR ( fromwebbook.nist.gov ) Absorbance Wavenumber

  6. The Hydrogen Bond • ”A hydrogen bond exists between the functional group, A-H, and an atom or a group of atoms, B, in the same or different molecules when (a) there is evidence of bond formation (association or chelation) (b) there is evidence that this new bond linking A-H and B specifically involves a hydrogen atom already bonded to A” G.C.Pimentel, A.L.McClellan, The Hydrogen Bond, 1960

  7. The Hydrogen Bond Strong Medium Weak

  8. The Hydrogen Bond Strong Medium Weak

  9. d+ d+ d- d+ d- d+ The Hydrogen Bond • ”A hydrogen atom with only one stable orbital cannot form more than one pure covalent bond and the attraction of the two atoms observed in hydrogen bond formation must be due largely to ionic forces”” • L.Pauling, The Nature of Chemical Bond, 1939

  10. The Hydrogen Bond • YHB = aYa + bYb + cYc + dYd + eYe Ya A-H…B covalent A-H bond Yb A- -H+ …B ionic A-H bond Yc A- -H…B+ charge transfer , A…B bond Yd A+ -H- …B ionic A-H bond Ya A-H- …B+ charge transfer, H…B bond C.A.Coulson, In Hydrogen Bonding, D.Hadzi (Ed.) 1959, pp. 339-360. O-H … O with O … O = 2.8 Å Yb + Ydcontribute 65 % of the hydrogenbondenergy

  11. Interaction energy of a H-bond • Supermolecular approach Eint = EAB – (EA + EB)

  12. Interaction energy decomposition scheme

  13. HCN…HCN ( MP2 ) A.Heikkilä, J.Lundell, J.Phys.Chem. A 104, 2000, 6637-6643

  14. Symmetry-Adapted Perturbation Theory (SAPT) K.Szalewicz, K.Patkowski, B.Jeziorski ,Struct.Chem. 116, 2005, 43-117

  15. R.A.Christie, K.D.Jordan, Struct.Chem. 116, 2005, 27-41

  16. Having more than two molecules? S.S.Xantheas Struct.Chem. 116, 2005, 119-148

  17. S.S.Xantheas Struct.Chem. 116, 2005, 119-148

  18. Non-additive (cooperative) effects

  19. S.S.Xantheas Struct.Chem. 116, 2005, 119-148

  20. Basis set superposition error (BSSE) HNC…HCN The ”cure”: Counterpoise correction (Boys-Bernardi ) Not perfect basis sets, so needs to borrow from the neighbour…

  21. S.S.Xantheas Struct.Chem. 116, 2005, 119-148

  22. J.R.Lane, H.G.Kjaergaard, J.Phys.Chem. 131, 2009, 034307

  23. Changesuponhydrogenbonding… G.A.Jeffrey, An Introduction to Hydrogen Bonding, 1997

  24. hn t-HCOOH HCOOH photochemistry in matrices H2O + CO vs CO2 + H2 J.Lundell, M.Räsänen, J.Phys.Chem. 99, 1995, 14301.

  25. CCSD(T)/6-311++G(2d,2p) 2.323 2.365 Eint,cp = -3.17 kJ mol-1 Eint,cp = -5.29 kJ mol-1 H2O...CO : Two stable complex structures J.Lundell, J.Phys.Chem. 99, 1995,14290J.Lundell, Z.Latajka, J.Phys.Chem. A 101, 1997, 5004

  26. HOH...CO exp. Dn calc. Dw 3724 -9 3864 -17 3628 -9 3826 -22 1596 +2 1656 +10 2148 +10 2130 +13 JPC 99, 1995, 14290: MP2/6-311++G(2d,2p) JPC 99, 1995, 14301: Ng-matrices H2O...CO : Experiments • In situ photolysis of formic acid in a solid argon matrix

  27. argon krypton xenon H2O...CO : Experiments • Annealing the matrix after photolysis

  28. CO stretch HOH...CO HOH...OC Gas phase 2154 +11 Ar 2149 +11 Kr 2145 +9 2130 -6 Xe 2142 +8 2128 -5 calc. 2130 +10 2118 -2 MP2/6-311++G(2d,2p) H2O...CO : Experiments • Both HOH...CO and HOH...OC can be made

  29. Can we do more?

  30. Anharmonic calculations: cc-VSCF • Vibrational Schrödinger equation in mass-weighted normal mode coordinates • single-mode wavefunctions, energies and effective potentials 2nd order perturbation theory for correlation effects between different vibrational modes pairwise interactions between normal modes

  31. Anharmonic calculations: cc-VSCF • Grid-approach of PES: - 8  8 or 16  16 grids - points chosen equidistantly over an interval defined by the harmonic frequency of a vibrational mode:Qmax~ inverse square root of the frequencyG.M.Chaban, J.O.Jung, R.B.Gerber, J.Phys.Chem. A 104, 2000, 2772 • Implemented in GAMESS-US

  32. MP2/aug-cc-pVTZ + cc-VSCF * CO2...H2

  33. MP2/aug-cc-pVTZ + cc-VSCF

  34. MP2/6-311++G(2d,2p) cis trans 4544 cm-1 Exp: 4842 cm-1 1488 cm-1 Exp: 1362 cm-1 The formic acid monomer: Two conformers

  35. trans IR cis IR-pumping at 6934 cm-1 (2 nOH) M.Pettersson, J.Lundell, L.Khriachtchev, M.Räsänen, JACS 119, 1997, 11715

  36. HCOOH anharmonic calculations trans-HCOOH anharmonic harmonic cis-HCOOH E.M.S.Macoas, J.Lundell, M. Pettersson, L.Khriachtchev, R.Fausto, M.Räsänen, J.Mol.Spectrosc. 219, 2003, 70.

  37. vibr exc tunneling Tunneling can be stopped by complexation X K. Marushkevich, L.Khriachtchev, M.Räsänen, J.Phys.Chem. A 111, 2007, 2040 Isomerisation of formic acid: The monomer trans cis

  38. FAD-tt1 1.684 1.684 Ecp,int (MP2)= -66.71 kJ mol-1 FAD-tt4 1.927 1.968 Ecp,int (MP2)= -28.68 FAD-tt2 1.774 2.337 Ecp,int (MP2)= -37.21 FAD-tt3 2.408 2.509 Ecp,int (MP2)= -11.81 FAD-tt5 FAD-tt6 1.896 2.417 2.406 2.417 Ecp,int (MP2)= -23.36 Ecp,int (MP2)= -15.39 The trans-trans formic acid dimers MP2/6-311++G(2d,2p)

  39. MP2/6-311++G(2d,2p) cc-VSCF without mode coupling The trans-trans –dimer (FAD-tt1) FAD-tt1 in solid argon From M.Gantenberg, M.Halupka, W.Sander, Chem.Eur.J. 6, 2000, 1865

  40. FAD-tt1 FAD-tt2 Solid argon A.Olbert-Majkut, J.Ahokas, J.Lundell, M.Pettersson, Chem.Phys.Lett. 468, 2009, 176.

  41. Computed relative energies FAD-cc3 FAD-cc4 FAD-cc2 FAD-tc4 FAD-cc1 FAD-cc5 FAD-tc5 FAD-tt3 FAD-tc3 FAD-tt6 FAD-tc2 FAD-tt5 FAD-tc1 FAD-tt4 FAD-tt2 cis-FA Experimentally observed trans-FA FAD-tt1 excitation at 3168 cm-1 (C-H str) The trans-trans formic acid dimers FAD-tt3 FAD-tt6

  42. FAD-tt1 (CD) Excitation at 3540 cm-1 FAD-tt2 ( * ) * Pumping O-H str in trans-trans dimer ? * * * * K.Marushkevich, L.Khriachtchev, J.Lundell, M.Räsänen, JACS 128, 2006, 12060

  43. FAD-tc1 FAD-tc2 1.761 1.950 1.852 2.287 Ecp,int (MP2)= -41.31 kJ mol-1 Ecp,int (MP2)= -38.02 FAD-tc4 FAD-tc3 2.502 1.814 2.387 Ecp,int (MP2)= -29.79 Ecp,int (MP2)= -12.74 FAD-tc5 1.857 Ecp,int (MP2)= -23.20 The cis-trans formic acid dimers MP2/6-311++G(2d,2p)

  44. hn (IR) 1.761 1.774 2.287 2.337 FAD-tc1 FAD-tc1 FAD-tt2 x 5 x 1 FAD-tc1 FAD-tt2 FAD-tt2 trans-FA trans-FA cc-VSCF//MP2 computed wavenumbers [cm-1] The cis-trans formic acid dimers

  45. 4543.7 cm-1 4771.5 cm-1 1488.0 cm-1 1180.3 cm-1 The cis-trans formic acid dimers MP2/6-311++G(2d,2p)

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