Pure Appl. Chem., 2011, Vol. 83, No. 8, pp. 1619-1636
http://dx.doi.org/10.1351/PAC-REP-10-01-01
Published online 2011-07-08
PHYSICAL AND BIOPHYSICAL CHEMISTRY DIVISION
Defining the hydrogen bond: An account (IUPAC Technical Report)
Elangannan Arunan1*, Gautam R. Desiraju2, Roger A. Klein3, Joanna Sadlej4, Steve Scheiner5, Ibon Alkorta6, David C. Clary7, Robert H. Crabtree8, Joseph J. Dannenberg9, Pavel Hobza10, Henrik G. Kjaergaard11, Anthony C. Legon12, Benedetta Mennucci13 and David J. Nesbitt14
1 Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore 560012, India
2 Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012, India
3 30 Kimberley Road, Chesterton, Cambridge, CB4 1HH, UK
4 Department of Chemistry, Laboratory of Intermolecular Interactions, University of Warsaw, Warsaw, PL-02093, Poland
5 Department of Chemistry and Biochemistry, 0300 Old Main Hall, Utah State University, Logan, UT 84322, USA
6 Medicinal Chemistry Institute, Juan de la Cierva 3, Madrid E-28006, Spain
7 Department of Physical and Theoretical Chemistry, Oxford University, South Parks Road, Oxford OX1 3QZ, UK
8 Department of Chemistry, 225 Prospect Street, Yale University, New Haven, CT 06511-8499 USA
9 Department of Chemistry and Biochemistry, City University of New York, Hunter College, 695 Park Avenue, New York, NY 10065, USA
10 Institute of Organic and Biochemistry, Academy of Sciences of Czech Republic, Flemingovo nam 2, Praha CZ 16610, Czech Republic
11 Department of Chemistry, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen Ø, Denmark
12 School of Chemistry, University of Bristol, Bristol BS8 1TS, UK
13 Department of Chemistry, University of Pisa, Via Risorgimento 35 Pisa 1-56125, Italy
14 Department of Chemistry and Biochemistry, University of Colorado, Boulder, CO 80309, USA
Abstract:
The term “hydrogen bond” has been used in the literature for nearly a century now. While its importance has been realized by physicists, chemists, biologists, and material scientists, there has been a continual debate about what this term means. This debate has intensified following some important experimental results, especially in the last decade, which questioned the basis of the traditional view on hydrogen bonding. Most important among them are the direct experimental evidence for a partial covalent nature and the observation of a blue-shift in stretching frequency following X–H···Y hydrogen bond formation (XH being the hydrogen bond donor and Y being the hydrogen bond acceptor). Considering the recent experimental and theoretical advances, we have proposed a new definition of the hydrogen bond, which emphasizes the need for evidence. A list of criteria has been provided, and these can be used as evidence for the hydrogen bond formation. This list is followed by some characteristics that are observed in typical hydrogen-bonding environments.
