Marie-Claire Bellissent-Funel

Hydrogen Bond Networks

Preface. Section A: Modelling and Hydrogen-Bond Structures. Hydrogen Bonding and the Fragility of Supercooled Liquids and Biopolymers C.A. Angell, C. Alba-Simionesco, J. Fan, J.L. Green. Hydrogen Bonding and Molecular Mobility in Aqueous Systems A. Geiger, T. Kowall. Structural and Dynamical Quantum Effects in Aqueous Solution P.J. Rossky. Novel Features in the Equation of State of Metastable Water P.H. Poole, F. Sciortino, U. Essmann, M. Hemmati, H.E. Stanley, C.A. Angell. The Role of H-Bonds in the Formation of Ices J-C Li, D.K. Ross. Radial Distribution Function of Heavy Water Steam A. Fontana, P. Postorino, M.A. Ricci, A.K. Soper. Molecular Dynamics on a Water Model with Polarizability and Hyperpolarizability G. Ruocco, M. Sampoli. M.D. Simulations of Stretched TIP4P--Water in the Supercooled Regime G. Ruocco, M. Sampoli, A. Torcini, R. Vallauri. Anomalous Sound Dispersion in Liquid Water U. Balucani, G. Ruocco, M. Sampoli, A. Torcini, R. Vallauri. Sound Propagation in Hydrogen Bonded Molecular Liquids: the Case of Liquid Water F. Sciortino, S. Sastry. Orientational Correlations in Hydrogen Bonded Networks A.K. Soper. Are Hydrogen Bonds Present in Hydrogen Halides Liquids Other than HF? C. Andreani, F. Menzinger, M. Nardone, F.P. Ricci, M.A. Ricci, A.K. Soper. Investigation of the Structure of Liquid Formic Acid I. Bako, P. Jedlovszky, G. Palinkas, J.C. Dore. Section B: Spectroscopic Studies, Complexes and Solutions. Incoherent Inelastic Neutron Scattering from Liquid Water: a Computer Simulation Study J.-C. Leicknam, M. Diraison, G. Tarjus, S. Bratos. The Observation of Different Strengths of H-Bonds in Ices J-C Li, D.K. Ross, M.H.B.Hayes, W.F. Sherman, M. Adams. IR Spectra and Dynamics of H2O (D2O, HDO) Molecules in a Still Poorly Known Liquid: Water Y. Marechal. Low Frequency Raman Spectra from Anhydrous Sulfuric and Chlorosulfonic Acids and Liquid Water, Disruption of Tetrahedral Hydrogen Bonding Relation to Water Structure Y.C. Chu, G.E. Walrafen. Picosecond Holeburning Spectroscopy in the Infrared of Water and Other Hydrogen-Bonded Systems A. Laubereau, H. Graener. Low Frequency Raman Spectra in Water by Normal Mode Analysis S. Sastry, H.E. Stanley, F. Sciortino. Light Scattering from Liquid Water M.A. Ricci. Dielectric Properties of Aqueous Solutions G. Salvetti, E. Tombari. Formic Acid, Ethanol in Vycor Glass and Water in Aluminosilicate Zeolites C.K. Loong, F. Trouw, L.E. Iton. Application of the Reactive Flux Formalism to Study Water Hydrogen Bond Dynamics A. Luzar, D. Chandler. Temperature Dependence of Ion Solvation Dynamics in Liquid Water H. Resat, F.O. Raineri, B-C. Perng, H.L. Friedman. Theoretical Simulation of OH and OD Stretching Bands of Isotopically Diluted HDO Molecules in Lithium Formate Solution M.J. Wojcik, K. Hermansson, J. Lindgren, L. Ojamae. Influence of Water Molecules on the Nucleation Rate of Polymorphic Complexes with Different Conformations in Solution S. Petit, G. Coquerel, G. Perez. Hydrogen-Bond Nature in Solids Based on Nuclear Quadrupole Resonance Spectroscopy Studies B. Nogaj. Simulation of Liquid Mixtures G. Palinkas, K. Heinzinger. Section C: Networks, Interfaces and Confined Geometry. Structure and Dynamics of Water in Confined Geometry S-H. Chen, M.-C. Bellissent-Funel. Structure and Dynamics of Water at Interfaces P.J. Rossky. Hydrogen B

Harmonicity in slow protein dynamics

The slow dynamics of proteins around its native folded state is usually described by diffusion in a strongly anharmonic potential. In this paper, we try to understand the form and origin of the anharmonicities, with the principal aim of gaining a better understanding of the principal motion types, but also in order to develop more efficient numerical methods for simulating neutron scattering spectra of large proteins. First, we decompose a molecular dynamics (MD) trajectory of 1.5 ns for a C-phycocyanin dimer surrounded by a layer of water into three contributions that we expect to be independent: the global motion of the residues, the rigid-body motion of the sidechains relative to the backbone, and the internal deformations of the sidechains. We show that they are indeed almost independent by verifying the factorization of the incoherent intermediate scattering function. Then, we show that the global residue motions, which include all large-scale backbone motions, can be reproduced by a simple harmonic model which contains two contributions: a short-time vibrational term, described by a standard normal mode calculation in a local minimum, and a long-time diffusive term, described by Brownian motion in an effective harmonic potential. The potential and the friction constants were fitted to the MD data. The major anharmonic contribution to the incoherent intermediate scattering function comes from the rigid-body diffusion of the sidechains. This model can be used to calculate scattering functions for large proteins and for long-time scales very efficiently, and thus provides a useful complement to MD simulations, which are best suited for detailed studies on smaller systems or for shorter time scales.

Structural study of water confined in porous glass by neutron scattering

In order to study the structural properties of water at interfaces, we performed neutron scattering experiments of water confined inside interconnected pores of Vycor glass. The structure factors and the corresponding radial distribution functions of the confined water have been determined as a function of temperature from 35 °C down to −100 °C and for two levels of hydration of the glass (full and partial hydration). At 27 °C, the structure factor of confined water is very similar to that of bulk water. When decreasing the temperature, we show that it is possible to supercool water inside pores of Vycor but not to the extent expected for such a small confining space. In fact the presence of large hydrophilic silica interface enhances the nucleation of ice. The observed phase of ice is the cubic ice which appears at about −18 °C in the full hydrated Vycor. The other interesting observation is a greater degree of supercooling of water in partially hydrated samples of Vycor compared to fully hydrated ones. ...

A neutron scattering study of liquid D2O under pressure and at various temperatures

A structural investigation of liquid D2O was performed by neutron scattering at pressures up to 6 kbar and in a range of temperatures from 53 down to −65 °C. Some comparison is made with Monte Carlo (MC) and molecular dynamics (MD) simulations. In particular, the results are used to test some recent MD simulations leading to a phase diagram which provides a complete picture of the stable and metastable behavior of water and incorporates the two amorphous ices of water.

Structure of high‐density amorphous water. II. Neutron scattering study

High‐density amorphous water is studied by neutron scattering in a Q range extending to 16 A−1. The low density form of amorphous water is also analyzed and compared with previous results. There are very important differences in the composite pair correlation functions of the two forms of amorphous ice, in particular beyond the first nearest‐neighbors distance. We conclude that the hydrogen bond network is strongly deformed in a manner analogous to that found in water at high temperature. This is in contrast with the behavior of the pair correlation function of low‐density amorphous water, which is closer to that of supercooled water.

Hydration-Coupled Dynamics in Proteins Studied by Neutron Scattering and NMR: The Case of the Typical EF-Hand Calcium-Binding Parvalbumin

The influence of hydration on the internal dynamics of a typical EF-hand calciprotein, parvalbumin, was investigated by incoherent quasi-elastic neutron scattering (IQNS) and solid-state 13C-NMR spectroscopy using the powdered protein at different hydration levels. Both approaches establish an increase in protein dynamics upon progressive hydration above a threshold that only corresponds to partial coverage of the protein surface by the water molecules. Selective motions are apparent by NMR in the 10-ns time scale at the level of the polar lysyl side chains (externally located), as well as of more internally located side chains (from Ala and Ile), whereas IQNS monitors diffusive motions of hydrogen atoms in the protein at time scales up to 20 ps. Hydration-induced dynamics at the level of the abundant lysyl residues mainly involve the ammonium extremity of the side chain, as shown by NMR. The combined results suggest that peripheral water-protein interactions influence the protein dynamics in a global manner. There is a progressive induction of mobility at increasing hydration from the periphery toward the protein interior. This study gives a microscopic view of the structural and dynamic events following the hydration of a globular protein.

Is there a liquid-liquid phase transition in supercooled water?

Previous studies of the structure of liquid water under pressure performed by neutron diffraction, allowed us to establish two structural limits in liquid water. These two limits are closely connected to the two known forms of amorphous ice : the low density amorphous ice (LDA) and the high density amorphous ice (HDA). In the present paper, we propose some interpretation of our data in terms of a two level type model of water. This leads to show some evidence of a liquid-liquid phase transition in liquid supercooled water. The result looks in agreement with recent computer simulations that incorporate the two forms of amorphous ice.

The structure of supercritical heavy water as studied by neutron diffraction

Neutron diffraction experiments of heavy water at several supercritical states (380<T<500 °C and 200<P<900 bar) corresponding to densities ranging from 0.2 to 0.7 g/cm3 are performed. They allow the static structure factor and the pair correlation function to be derived once absorption, multiple scattering, and inelasticity corrections have been made. The experimental results are compared with previous data obtained by Postorino et al. [Nature 366, 668 (1993)] and with new molecular dynamics simulations using the extended simple point charge (SPCE) potential. They lead to the conclusion that hydrogen bonding is still present in supercritical water. This conclusion does not agree with the previous findings of Postorino et al. but looks rather in agreement with the results of computer simulations.

X‐ray and neutron scattering studies of the structure of water at a hydrophobic surface

The structure of water in contact with a hydrophobic surface, namely, activated carbon, is studied using both x‐ray and neutron scattering techniques. The structure factors and the corresponding radial distribution functions are determined for several levels of hydration, at room temperature and down to 77 K. At high water content (∼200%), the properties of water are very similar to those of bulk water; in partially hydrated samples (<50%), the molecular structure exhibits change of its local environment within particular a distortion at the level of the second neighbors, and water does not crystallize when the temperature is lowered.

Slow dynamics of water molecules on the surface of a globular protein

Water is essential for the stability and function of biological macromolecules. High-resolution quasi-elastic neutron scattering studies of the translational dynamics of water molecules on the surface of a deuteriated protein are presented. The quasi-elastic spectra from the interfacial H2O are analysed by a confined diffusion model to obtain the elastic incoherent structure factor (EISF), the short-time self-diffusion constant (D) and the residence time, τ0, as functions of coverage and temperature. The combined effects of the hydration level and temperature on the retardation of the single-particle motions are discussed in the light of available NMR relaxation data and of a well known model of α-relaxation from the theory of kinetic glass transitions in dense supercooled fluids. The vibrational density of states of interfacial water is presented as a function of temperature and for two levels of hydration of the protein.