top of page

Intermolecular Interactions - Cause & Effect 

Chemical Physics Group


Our group is currently seeking applications for Postdoctoral position in MD simulations. Interested candidates may apply

Research Highlights

Proton Transfer Reactions

The ability of solvent to abstract a proton from a solute depends on the  solvent distribution around the solute. Recently, we have shown that for a spontaneous proton transfer from a phenol moiety embedded in ammonia clusters, the  ammonia molecules must organize around the OH group of phenol in such a way that they project an electric field in excess of the critical electric field of 285 MV cm-1 along the O–H bond, which drives the proton transfer process with a response time of about 70 fs. The proton transfer is  instantaneous and follows a curvilinear path which includes the O–H bond elongation and out-of-plane movement of the proton can be referred to as  “Bend-to-Break”  process

Photodissociation Dynamics

The dissociative photoionization of xylenes and mesitylene leading to the formation of methyl radical and corresponding co-fragment was investigated by velocity map imaging technique. The total translational energy profiles were almost identical for the methyl fragment in all cases, except for the co-fragment profile for m-xylene which was attributed to probe induced dissociation. The profiles are rationalized based on {sp2}C–C{sp3} bond dissociation in the cationic state following a resonant [1+1+1] 3-photon process. Fitting the profiles to an empirical function reveals that the corresponding dynamics is insensitive to the position of substitution but marginally dependent on the number of methyl groups. 

Classifying Peptide Aggregation

Protein-protein interaction is an important phenomenon in many biological. In this work we developed a new and robust method analyse peptide aggregation. In this method, the inter-peptide Cα-Cα pairwise distances are binarily encoded  leading to formation of an Aggregation Matrix, which can be used enumerate, hierarchically order, and structurally classify peptide Aggregates. The USP of this method provides the residue-wise information in the aggregation calculated by using just 2D matrix.

About Us

The "Chemical Physics Group" at the Department of Chemistry, Indian Institute of Technology Bombay is a multidisciplinary research group headed by Prof. G. Naresh Patwari. Research work in this group focuses mainly on phenomena that are influenced by intermolecular interactions such as hydrogen bonding and π-stacking. The group uses several experimental and computational methodologies to probe phenomena driven by intermolecular interactions.  The group has two "state-of-the-art" "home-built" spectrometers that couple molecular beams with various laser spectroscopic techniques, wherein fluorescence and mass detection techniques are used in addition to ion imaging.  Moreover, group also uses IIT Bombay's supercomputing facility to carry out electronic structure and molecular dynamics calculations. Using experiment and/or computations, the group works on several interesting research themes such as (i) molecular aggregation and polymorphism, (ii) intermolecular coulombic decay, (iii) hydrogen bond induced non-adiabatic dynamics, (iv) electric fields in proton transfer reactions, (v) vibrational Stark effect, (vi) etiology of nucleic acids, (vii) effect of organic fluorine on intermolecular interactions, (viii) molecular foldamers, (ix) ion sensing and others.  ​The research group is a amalgam of vibrant and motivated graduate students and postdoctoral fellows. One of the interesting aspects is that each member works in a different research problem making it a truly diversified and multidisciplinary research group. 

Contact Us

Last Updated: June 16, 2020

Department of Chemistry

Indian Institute of Technology Bombay

Powai, Mumbai 400076 INDIA

+91-22-25767182 (Office)

+91-22-25764191 (Laboratory)

Email: naresh[at]

Thanks for submitting!

bottom of page