Short CV
Enrique got his Licenciatura (equivalent to Bachelor and Master degrees) in Physics at the University of Barcelona in 1987. After a first period working as teacher in high schools and in private companies, he started his PhD on experimental electron density studies at the Institut de Ciència de Materials de Barcelona (CSIC) in collaboration with the laboratory of crystallography of Nancy (supervisors Profs. Elies Molins and Claude Lecomte).
He defended his PhD in 1994 at the University of Barcelona. Then, he spent the next two years (1995-96) in a postdoctoral position at the laboratory of crystallography of Nancy under the supervision of Prof. Claude Lecomte.
He continued to work in the same laboratory during 1997, with a non-permanent lecturer position, teaching at the Faculties of Sciences and Pharmacy of Nancy.
In 1998, he came back to the Institut de Ciència de Materials de Barcelona (CSIC) with a research contract.
In September 1999, he moved to Dijon to work as crystallographer in a molecular chemistry laboratory at the University of Bourgogne, where he got a permanent position of associated professor in chemical crystallography in 2002.
In 2005, he defended his Habilitation in this domain at the University of Bourgogne. In 2006, he left Dijon to move again to Nancy, where he got a permanent of position of professor of physics in the laboratory of crystallography of Nancy.
In 2011, he got the position of full professor in crystallography in the same laboratory, where he is still working.
Enrique has served as vice-dean of the Faculty of Sciences of Nancy during the period 2013-23, in charge of the scientific domains of physics, chemistry, geological sciences and mechanics.
In research, Enrique is mainly interested in interatomic and intermolecular interactions, focusing on molecular assembly and molecular organisation in space, within the field of crystal engineering and in the framework of the structure-properties relationship. With this aim, he has developed his research in the study of factors influencing hydrogen bonding and sigma-hole interactions, from intra- and inter-molecular effects. The topological analyses of the electron density, the electrostatic potential and the Laplacian of the electron density, as well as the topographic analysis of the electric field lines in space are main tools in his research.
He has published more than 150 papers, with more than 10000 citations and the h-index of 42 (google scholar), and delivered more than 50 lectures at invited conferences and seminars.
Lecture 27: Enrique Espinosa
TOPOLOGICAL ANALYSIS OF THE ELECTROSTATIC POTENTIAL in MOLECULAR SYSTEMS
Enrique Espinosa
Université de Lorraine, CNRS, CRM2 (Laboratoire de Cristallographie, Résonance Magnétique et Modélisations), UMR 7036, F-54000 Nancy (France)
E-mail: enrique.espinosa@univ-lorraine.fr
The molecular electrostatic potential j(r) has been extensively used in the analysis of molecular recognition due to the electrostatic character of long-range interactions. In most cases, relevant features of j(r) are found in the outer molecular envelop, pointing its nucleophilic and electrophilic regions.
The topological analysis of j(r) has been developed in order to further exploit the information contained in this function. The gradient vector field of j(r) leads to a complete partition of the molecular space in disjoint regions, which are separated by zero-flux surfaces of the scalar field j(r). These surfaces define electrostatic basins, which are different from those obtained from the topological analysis of the electron density distribution r(r), called atomic basins. A most significant consequence of electrostatic basins enclosed by zero-flux surfaces of j(r) is that they define the regions of the real space with zero net charge. Additionally, the gradient function of j(r), which is the negative of the electric field (Ñj(r) = -e(r)), draws the force lines in the real space stablishing molecular communication.
In the first part of the talk we will see how the electric field lines are able to determine without ambiguity the true electrophilic and nucleophilic sites in molecules, and how they can accurately show the extension and shape of their influence zones in the space out of molecules (neutral, negatively and positively charged).
In the second part of the talk we will introduce the intersection of the gradient vector fields of j(r) and r(r). We will see how the particular positioning of their zero flux surfaces divide bonding regions in three parts, the central one (called electrostatic attraction region (EAR)) being involved in the main contribution to the electrostatic interaction. This topological and electrostatic description has permitted to understand, and to explain, the paradoxical situation of anion-anion and cation-cation aggregates, which will be presented in the lecture.
References
“Zero-flux surfaces of the electrostatic potential: The border of influence zones of nucleophilic and electrophilic sites in crystalline environment”, I. Mata, E. Molins, E. Espinosa, J. Phys. Chem. A, 2007, 111, 39, 9859-9870
“Topological properties of the electrostatic potential in weak and moderate N…H hydrogen bonds”, I. Mata, E. Molins, I. Alkorta, E. Espinosa, J. Phys. Chem. A, 2007, 111, 28, 6425-6433
“Electrostatics at the Origin of the Stability of Phosphate-Phosphate Complexes Locked by Hydrogen Bonds”, I. Mata, I. Alkorta, E. Molins, E. Espinosa, ChemPhysChem, 2012, 13, 6, 1421-1424
“Tracing environment effects that influence the stability of anion-anion complexes: The case of phosphate-phosphate interactions”, I. Mata, I. Alkorta, E. Molins, E. Espinosa, Chem. Phys. Lett., 2013, 555, 106-109
“The Paradox of Hydrogen-Bonded Anion Anion Aggregates in Oxoanions: A Fundamental Electrostatic Problem Explained in Terms of Electrophilic…Nucleophilic Interactions”, I. Mata, E. Molins, I. Alkorta, E. Espinosa, J. Phys. Chem. A, 2015, 119, 1, 183-194
“Charged versus Neutral Hydrogen-Bonded Complexes: Is There a Difference in the Nature of the Hydrogen Bonds?”, I. Alkorta, I. Mata, E. Molins, and E. Espinosa, Chem. Eur. J., 2016, 22, 9226 – 9234.
“Energetic, Topological and Electric Field Analyses of Cation-Cation Nucleic Acid Interactions in Watson-Crick Disposition”, I. Alkorta, I. Mata, E. Molins and E. Espinosa
ChemPhysChem, 2019, 20, 148-158