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Department of Chemistry, University of Jyväskylä The Hydrogen Bond Jan Lundell Department of Chemistry, University of Jyväskylä.

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Presentation on theme: "Department of Chemistry, University of Jyväskylä The Hydrogen Bond Jan Lundell Department of Chemistry, University of Jyväskylä."— Presentation transcript:

1 Department of Chemistry, University of Jyväskylä The Hydrogen Bond Jan Lundell Department of Chemistry, University of Jyväskylä

2 Department of Chemistry, University of Jyväskylä The Hydrogen Bond

3 Department of Chemistry, University of Jyväskylä The Hydrogen Bond AdenineThymine Cytosine Guanine Peter Agre (Nobel Prize, 2003): The purest form of hydrogen bond there is…

4 Department of Chemistry, University of Jyväskylä 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 Department of Chemistry, University of Jyväskylä The Hydrogen Bond Wavenumber Absorbance HCOOH in the gas phase – IR ( from webbook.nist.gov )

6 Department of Chemistry, University of Jyväskylä 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 Department of Chemistry, University of Jyväskylä bond distance A-H  H...B A-H < H...BA-H << H...B H...B (Å)   A...B (Å) bond angle (º) binding energy (kJ/mol) < 15 StrongMediumWeak The Hydrogen Bond

8 Department of Chemistry, University of Jyväskylä StrongMediumWeak The Hydrogen Bond dimers of strong acids and bases in the gas phase acidsdimers of weak acids and bases in the gas phase Acid saltsalcohols, phenols C-H...O/N Proton spongeshydrates O/N-H...  HF complexesall biological molecules dihydrogen bonds

9 Department of Chemistry, University of Jyväskylä 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 Department of Chemistry, University of Jyväskylä The Hydrogen Bond  HB = a  a + b  b + c  c + d  d + e  e  a A-H…Bcovalent A-H bond  b A - -H + …Bionic A-H bond  c A - -H…B + charge transfer, A…B bond  d A + -H - …Bionic A-H bond  a A-H - …B + charge transfer, H…B bond C.A.Coulson, In Hydrogen Bonding, D.Hadzi (Ed.) 1959, pp O-H … O with O … O = 2.8 Å  b +  d contribute 65 % of the hydrogen bond energy

11 Department of Chemistry, University of Jyväskylä Interaction energy of a H-bond Supermolecular approach E int = E AB – (E A + E B )

12 Department of Chemistry, University of Jyväskylä Interaction energy decomposition scheme

13 Department of Chemistry, University of Jyväskylä HCN…HCN ( MP2 ) A.Heikkilä, J.Lundell, J.Phys.Chem. A 104, 2000,

14 Department of Chemistry, University of Jyväskylä K.Szalewicz, K.Patkowski, B.Jeziorski,Struct.Chem. 116, 2005, Symmetry-Adapted Perturbation Theory (SAPT)

15 Department of Chemistry, University of Jyväskylä R.A.Christie, K.D.Jordan, Struct.Chem. 116, 2005, 27-41

16 Department of Chemistry, University of Jyväskylä S.S.Xantheas Struct.Chem. 116, 2005, Having more than two molecules?

17 Department of Chemistry, University of Jyväskylä

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19 S.S.Xantheas Struct.Chem. 116, 2005,

20 Department of Chemistry, University of Jyväskylä Non-additive (cooperative) effects

21 Department of Chemistry, University of Jyväskylä S.S.Xantheas Struct.Chem. 116, 2005,

22 Department of Chemistry, University of Jyväskylä Basis set superposition error (BSSE) Not perfect basis sets, so needs to borrow from the neighbour… The ”cure”: Counterpoise correction (Boys-Bernardi ) HNC…HCN

23 Department of Chemistry, University of Jyväskylä

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25 S.S.Xantheas Struct.Chem. 116, 2005,

26 Department of Chemistry, University of Jyväskylä J.R.Lane, H.G.Kjaergaard, J.Phys.Chem. 131, 2009,

27 Department of Chemistry, University of Jyväskylä G.A.Jeffrey, An Introduction to Hydrogen Bonding, 1997 Changes upon hydrogen bonding…

28 Department of Chemistry, University of Jyväskylä HCOOH photochemistry in matrices J.Lundell, M.Räsänen, J.Phys.Chem. 99, 1995, t-HCOOH h H 2 O + CO vs CO 2 + H 2

29 Department of Chemistry, University of Jyväskylä H 2 O...CO : Two stable complex structures CCSD(T)/ G(2d,2p) E int,cp = kJ mol -1 E int,cp = kJ mol -1 J.Lundell, J.Phys.Chem. 99, 1995,14290 J.Lundell, Z.Latajka, J.Phys.Chem. A 101, 1997, 5004

30 Department of Chemistry, University of Jyväskylä H 2 O...CO : Experiments In situ photolysis of formic acid in a solid argon matrix  calc.  exp. JPC 99, 1995, 14290: MP2/ G(2d,2p) JPC 99, 1995, 14301: Ng-matrices HOH...CO

31 Department of Chemistry, University of Jyväskylä H 2 O...CO : Experiments Annealing the matrix after photolysis argonkryptonxenon

32 Department of Chemistry, University of Jyväskylä H 2 O...CO : Experiments Both HOH...CO and HOH...OC can be made calc Xe Kr Ar Gas phase HOH...COHOH...OC MP2/ G(2d,2p) C  O stretch

33 Department of Chemistry, University of Jyväskylä Can we do more?

34 Department of Chemistry, University of Jyväskylä 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

35 Department of Chemistry, University of Jyväskylä 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: Q max ~ inverse square root of the frequency G.M.Chaban, J.O.Jung, R.B.Gerber, J.Phys.Chem. A 104, 2000, 2772 Implemented in GAMESS-US

36 Department of Chemistry, University of Jyväskylä * CO 2...H 2 MP2/aug-cc-pVTZ + cc-VSCF

37 Department of Chemistry, University of Jyväskylä MP2/aug-cc-pVTZ + cc-VSCF

38 Department of Chemistry, University of Jyväskylä

39 MP2/ G(2d,2p) 4544 cm cm -1 trans cis Exp: 4842 cm -1 Exp: 1362 cm -1 The formic acid monomer: Two conformers

40 Department of Chemistry, University of Jyväskylä M.Pettersson, J.Lundell, L.Khriachtchev, M.Räsänen, JACS 119, 1997, IR-pumping at 6934 cm -1 (2 OH ) trans cis IR

41 Department of Chemistry, University of Jyväskylä HCOOH anharmonic calculations E.M.S.Macoas, J.Lundell, M. Pettersson, L.Khriachtchev, R.Fausto, M.Räsänen, J.Mol.Spectrosc. 219, 2003, 70. trans-HCOOH cis-HCOOH harmonic anharmonic

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

43 Department of Chemistry, University of Jyväskylä FAD-tt E cp,int (MP2)= kJ mol -1 FAD-tt E cp,int (MP2)= FAD-tt E cp,int (MP2)= FAD-tt E cp,int (MP2)= FAD-tt E cp,int (MP2)= FAD-tt E cp,int (MP2)= MP2/ G(2d,2p) The trans-trans formic acid dimers

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

45 Department of Chemistry, University of Jyväskylä FAD-tt1 FAD-tt2 A.Olbert-Majkut, J.Ahokas, J.Lundell, M.Pettersson, Chem.Phys.Lett. 468, 2009, 176. Solid argon

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

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

48 Department of Chemistry, University of Jyväskylä FAD-tc E cp,int (MP2)= kJ mol -1 FAD-tc E cp,int (MP2)= FAD-tc E cp,int (MP2)= FAD-tc E cp,int (MP2)= FAD-tc E cp,int (MP2)= MP2/ G(2d,2p) The cis-trans formic acid dimers

49 Department of Chemistry, University of Jyväskylä cc-VSCF//MP2 computed wavenumbers [cm -1 ] x 5 FAD-tc1 FAD-tt2 trans-FA FAD-tc1 FAD-tt2 trans-FA x 1 FAD-tc1 FAD-tt h (IR) The cis-trans formic acid dimers

50 Department of Chemistry, University of Jyväskylä cm cm cm cm -1 The cis-trans formic acid dimers MP2/ G(2d,2p)

51 Department of Chemistry, University of Jyväskylä Photoisomerisation of formic acid dimers: Computed relative energies FAD-tt2 FAD-tt3 FAD-tt4 FAD-tt5 FAD-tc2 FAD-tt6 FAD-tt1 FAD-tc3 FAD-tc4 FAD-tc5 FAD-tc1 FAD-cc1 FAD-cc5 cis-FA trans-FA Experimentally observed FAD-cc4 FAD-cc2

52 Department of Chemistry, University of Jyväskylä FAD-cc1 E cp,int (MP2)= kJ mol FAD-cc E cp,int (MP2)= FAD-cc E cp,int (MP2)= FAD-cc E cp,int (MP2)= FAD-cc E cp,int (MP2)= MP2/ G(2d,2p) The cis-cis formic acid dimers

53 Department of Chemistry, University of Jyväskylä Computed relative energies FAD-tt2 FAD-tt3 FAD-tt4 FAD-tt5 FAD-tc2 FAD-tt6 FAD-cc3 FAD-tt1 FAD-tc3 FAD-tc4 FAD-tc5 FAD-tc1 FAD-cc4 FAD-cc2 FAD-cc1 FAD-cc5 cis-FA trans-FA Experimentally observed The cis-cis formic acid dimers ? ?

54 Department of Chemistry, University of Jyväskylä Current topics (Horizons in Hydrogen Bond Research, Paris, Sept 2009) Blue-shifting hydrogen bonds vs red-shifting hydrogen bonds Dihydrogen bonds (for example, H-O-H…HXeH ) Biomolecular systems - Water as biolubricant “Fast spectroscopy” (also dynamic simulations )


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