Theory Hydrogen Bond Cooperativity

An extension of the Ice Rule results in the building block of an ideal tetrahedron consisting two H2O molecules and four identical 0 H-0 bonds. 

The 0 H-0 bond performs as a pair of asymmetric, coupled, H-bridged oscillators. 

Under external stimulus, one part of the 0 H-0 bond serves as the muster and the other as a slave. Coulomb repulsion between electron pairs on oxygen dislocates the O atoms in the same direction under excitation along the 0 H—0 bond but by different amounts. The softer 0 H bond relaxes always more than the stiffer H-0 bond does. 

Relaxation of the H-0 bond energy determines the amount of the O Is energy shift, the high-frequency phonon relaxation, and the critical temperature change for phase transition. Relaxation of the 0 H bond energy shifts the frequenoy of 

Cooperative relaxation of the H-bond in length and energy and the associated binding electron entrapment and non-bonding electron polarization determine the 

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Wieczorek R, Dannenberg JJ (2003b) Hydrogen bond cooperativity, vibrational coupling, and dependence of helix stability on changes in amino acid sequence in small 3io-helical peptides. A density functional theory study. J Am Chem Soc 125 14065-14071... 

Theoretically, the problem has been attacked by various approaches and on different levels. Simple derivations are connected with the theory of extrathermodynamic relationships and consider a single and simple mechanism of interaction to be a sufficient condition (2, 120). Alternative simple derivations depend on a plurality of mechanisms (4, 121, 122) or a complex mechanism of so called cooperative processes (113), or a particular form of temperature dependence (123). Fundamental studies in the framework of statistical mechanics have been done by Riietschi (96), Ritchie and Sager (124), and Thorn (125). Theories of more limited range of application have been advanced for heterogeneous catalysis (4, 5, 46-48, 122) and for solution enthalpies and entropies (126). However, most theories are concerned with reactions in the condensed phase (6, 127) and assume the controlling factors to be solvent effects (13, 21, 56, 109, 116, 128-130), hydrogen bonding (131), steric (13, 116, 132) and electrostatic (37, 133) effects, and the tunnel effect (4,... 

In 1959, Eberson (1959, 1992) found that a family of derivatives of succinic acid shows a remarkably large negative cooperativity, i.e., gjj < < 1, which is difficult to explain on the basis of electrostatic theories only. We shall discuss these compounds in Subsection 4.8.6. At present, there is no satisfactory molecular interpretation of these findings. One of the more popular ideas, originally suggested by Jones and Soper (1936) and further elaborated upon by McDaniel and Brown (1953), is that an intramolecular hydrogen bond would facilitate the first dissociation of the proton, i.e., Kj becomes smaller (or Kj becomes larger). Also, the second proton will dissociate with more difficulty. The net effect would be a... 

Ireta J, Neugebauer J, Scheffler M, Rojo A, Galvan M (2003) Density functional theory study of the cooperativity of hydrogen bonds in finite and infinite o helices. J Phys Chem B 107 1432—1437... 

Suhai, S., Cooperative effects in hydrogen bonding Fourth-order many-body perturbation theory studies of water oligomers and of an infinite water chain as a model for ice, J. Chem. Phys. 101,9766-9782 (1994). 

Lastly, based on ab initio calculations that revealed that methyl acetate exhibits a favorable two-point interaction with CO2, Raveendran et al. suggested that acetylation of hydroxyl groups might be a possible method to solubilize hydroxylated compounds into CO2 (49). In theory, a hydrogen atom attached to the carbonyl carbon (a carbon) forms a weak yet cooperative C O hydrogen bond between the hydrogen and one of the oxygen... 

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