[1] Along with several scientific articles, he has authored three books, (i) Molecular Relaxation in Liquids[7], (ii) Water in Biological and Chemical Processes: From Structure and Dynamics to Function,[8] and (iii) Statistical Mechanics for Chemistry and Materials Science[9].

There he worked with renowned chemists such as David W. Oxtoby, Graham Fleming and Stuart Rice till 1983 when he shifted to the laboratory of Robert Zwanzig of the University of Maryland for a one-year stint.

[4] Bagchi returned to India in 1984 and joined Indian Institute of Science (IISc) at their Solid State and Structural Chemistry Unit as a lecturer and established his research group.

[12] His work has been published in reputed journals such as Nature,[13] PNAS,[14][15][16][17] PRL,[18] JACS,[19] JPC[20] and Chemical Reviews.

(ii)  Solvation dynamics of polar solutes in dipolar liquids (like water, ethanol) was a topic of huge contemporary interest from mid-eighties to late nineties.

Bagchi and co-workers came up with a microscopic theory of frequency and wave vector dependent dielectric function which included both rotational and translational degrees of freedom.

Due to the presence of orientational correlations, the longitudinal and transverse dielectric functions exhibit vastly different relaxation times at finite wave vectors.

[28][29] He has been selected as the 2021 recipient of the Joel Henry Hildebrand Award in the Theoretical and Experimental Chemistry of Liquids, by the American Chemical Society (ACS).