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, 8 ] and N-acetyl-L-glutamate [ 9 ] were reported. Hydrogen bonding plays an essential role in chemistry and especially in biology and is the most effective intermolecular interaction for organic compounds. It is more or less directional on one hand. On the other, its energy is sufficient for the formation of molecular networks and low enough to be destroyed in vivo . Pyridine based compounds are good candidates for such co-crystals based on hydrogen bonding. The presence of a hydroxyl group enhances such ability: in this case the formation of extended (from 1D to

Z. Phys. Chem. 219 (2005) 1635–1638  by Oldenbourg Wissenschaftsverlag, München Hydrogen Bonding Interaction between Methyl Methacrylate and Alcohols By P. Sivagurunathan, K. Dharmalingam∗, and K. Ramachandran Department of Physics, Annamalai University, Annamalai Nagar-608 002, Tamilnadu, India (Received July 9, 2005; accepted in revised form September 16, 2005) FTIR Spectroscopy / Alcohols / Hydrogen Bonding The hydrogen bonding between methyl methacrylate and primary, secondary and tertiary alcohols has been studied by using FTIR spectroscopic method. The

Introduction Flavoenzymes are a ubiquitous and diverse class of biological redox catalysts [1, 2]. The active site responsible for the activation of molecular oxygen has been established as the enzyme-bound 4a-hydroperoxyflavin [1–4]. One of the important roles of the proteins has been suggested to stabilize the intermediate 4a-hydroperoxyflavins by hydrogen bonds of the N(5) to the proteins. Otherwise, the 4a-hydroperoxyflavins undergo spontaneous elimination of H 2 O 2 to yield the oxidized flavins [5]. Thus, the intramolecular hydrogen bonding of N(5) to the

References 1 The Penguin Dictionary of Science , Penguin, London (1971). 2 L. Pauling. The Nature of the Chemical Bond , Cornell University Press, Ithaca, NY (1960). The first edition was published in 1939. 3 G. C. Pimentel, A. L. McClellan. The Hydrogen Bond , W. H. Freeman, San Francisco (1960). 4 D. Hadzi (Ed.). Hydrogen Bonding , Pergamon, London (1959). 5 W. C. Hamilton, J. A. Ibers. Hydrogen Bonding in Solids , W. A. Benjamin, New York (1968). 6 S. N. Vinogradov, R. H. Linnell. Hydrogen Bonding , Van Nostrand-Reinhold, New York (1971). 7 M. D. Joeston

depending on the weak bonding interactions, hydrogen bonds, that hold the rigid parts (i.e. those with the cations of higher valence) of their structures together, structural units, and interlayer spaces, with various mono-, di- or trivalent metal cations and molecular H 2 O [ 5 ], [ 10 ], [ 11 ], together. Therefore, it is essential to determine the details of hydrogen bonding in such minerals and phases, if we want to understand the details of their stabilities. Sayrite is a rare lead-uranyl-oxide mineral, with the composition Pb 2 [(UO 2 ) 5 (OH) 2 ]·4H 2 O, originally

Z. Phys. Chem. 221 (2007) 273–280 / DOI 10.1524/zpch.2007.221.2.273  by Oldenbourg Wissenschaftsverlag, München Solvent Effects on Hydrogen Bonding Between Ethanol and Acrylic Esters By P. Sivagurunathan, F. Liakath Ali Khan∗, and K. Ramachandran Department of Physics, Annamalai University, Annamalai Nagar, Tamilnadu-608 002, India (Received May 15, 2006; accepted in revised form November 11, 2006) FTIR Spectroscopy / Acrylic Esters / Hydrogen Bonding / 1 : 1 Complex / Solvent Effects The association between ethanol and acrylic esters (methyl acrylate, ethyl

References Velankar, S. & Cooper, S. L. (1998). Microphase Separation and Rheological Properties of Polyurethane Melts. 1. Effect of Block Length. Macromolecules 31, 9181-9192. DOI: 10.1021/ma9811472. Coleman, M. M., Lee, K. H., Skovranek, D. J. & Painter, P. C. (1986). Hydrogen bonding in polymers. 4. Infrared temperature studies of a simple polyurethane, Macromolecules , 19, 2149-2157. DOI: 10.1021/ma00162a008. Lee, H. S., Wang, Y. K. & Hsu, S. L. (1987). Spectroscopic analysis of phase separation behavior of model polyurethanes. Macromolecules , 20, 2089

Hydrogen Bonding of 2-Tetrazenes, 2 [1]. Synthesis and Structural Studies of Hydroxyalkyl-Substituted 2-Tetrazenes* Bernd Poratha, Paul Rademachera, Roland Boeseb, and Dieter Bläserb a Institut für Organische Chemie, Universität Essen, Universitätsstrasse 5-7, D-45117 Essen, Germany b Institut für Anorganische Chemie, Universität Essen, Universitätsstrasse 5, D-45117 Essen, Germany Reprint requests to Prof. Dr. Paul Rademacher. Fax: +49-(0)201-183-4252. E-mail: Z. Naturforsch. 57 b, 365–376 (2002); received January 30, 2002

1 Introduction Vibration levels need to be controlled in many applications to avoid structural instability and eliminate noise [ 1 ]. Small molecule/macromolecule hybrid damping materials provide a new way to reduce vibration by significantly improving the loss factor at low loading conditions. The damping properties of hybrid materials are directly related to the hydrogen bonding between the polymers and small molecules in the hybrid materials [ 2 ], [ 3 ], [ 4 ]. The self-assembly of condensed state structures and functionalization of macromolecule

Z. Phys. Chem. 224 (2010) 1185–1204 . DOI 10.1524.zpch.2010.6147 © by Oldenbourg Wissenschaftsverlag, München Probing the Equilibrium Size and Hydrogen Bonding Structure in Aqueous Aerosol Droplets By Lennart Treuel2, Jason R. Butler1, Graham Hargreaves1, and Jonathan P. Reid1,* 1 School of Chemistry, University of Bristol, Bristol, BS8 1TS, United Kingdom 2 Physikalische und Theoretische Chemie, Universität Duisburg-Essen, 45141 Essen, Germany Dedicated to Prof. Dr. Reinhard Zellner on the occasion of his 65th birthday (Received December 20, 2009; accepted April