Amit Kumar Paul
Associate Professor

Amit Kumar Paul
Associate Professor, Chemical Sciences

PhD: IACS Kolkata, 2013

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Previous appointments:

Post Doctoral Research Associate, Texas Tech University, Feb. 2013 - June 2016 (with Prof. William L. Hase)

Assistant Professor, Department of Chemistry, NIT Meghalaya, June 2016 - Dec. 2023

Associate Professor, Department of Chemistry, NIT Meghalaya, Dec 2023 - May 2024

Research interests:

Current Research Interests:

1. Chemical Dynamics Simulations using Machine Learning Approaches
2. Chemical dynamics simulations on reaction dynamics,Studies of chemical reactions in condensed phase
3. Energy Transfer dynamics in gas and condensed phase,Semiclassical dynamics on nonadiabatic processes
4. QM+MM dynamics in condensed phase molecular system
5. Quantum dynamics on adiabatic and diabatic potential energy surfaces

Contact:

Address:	Chemical Sciences Unified Academic Campus Bose Institute EN-80, Sector V Bidhan Nagar Kolkata - 700 091, India
E-Mail:	amit.paul[at]jcbose.ac.in

Research:

1.       Chemical Dynamics Studies using Machine Learning Approaches

Using machine-learned potential energy surfaces for the dynamics is an active field of research now-a-days. In our group, we are working on developning ML-based potential energy surfaces. In addition, we are looking at the prediction of the simulated properties, without actually running the simulations. [J. Chem. Phys. 158, 194104 (2023)]

2.   Simulating Intermolecular Collisional Energy Transfer and Chemical Reaction in Bath Model

A simulation bath model has been developed [J. Chem. Phys. 140, 194103 (2014)] to study collisional energy transfer phenomena. In this model, a 3D box implemented with periodic boundary conditions can be taken with a thousand or more solvent molecules. Any solvent bath density from liquid to gas can be considered. Collisional energy transfer as well as chemical reactions can be studied in this model. In the group, we have been performing many such projects.

3. Unimolecular Dissociation Reaction

Unimolecular dissociation is studied by chemical dynamics simulations of randomly excited clusters of aromatic molecules. Benzene dimer, benzene-hexafluorobenzene, benzene-hexachlorobenzene, etc. are studied at a temperature range of 700-2000 K. This temperature range is relevant for combustion chemistry. These studies provide detailed knowledge of their bindings and dynamical aspects.



4. Electronic Non-adiabatic Dynamics in Gas and Condensed Phase

It is well known that a strong or even a moderate coupling between the electronic states breaks down the Born-Oppenheimer (BO) approximation and the inclusion of non-adiabatic coupling terms into the Schrödinger equation becomes important. In spite of its wide applicability, a fully quantum mechanical dynamics is still impossible even with a huge computation facility of current time for systems of many degrees of freedom. Therefore, the classical mechanical molecular dynamics will be used as the workhorse for many coming years as well. It is of interest for our group is to study photochemical reactions of molecular systems using semiclassical molecular dynamics simulations.

5. Development of Two-Body Potential Energy Function

The potential energy surface (PES) of a molecular system holds many of its chemical properties. Dynamics, which is nothing but the spatial evolution of nuclei around the PES with time. The chemical dynamics simulations performed nowadays involve the integration of the classical equations of motion (Newtonian or Langevin), calculating the forces on atoms at each step either directly by electronic structure calculations, called direct dynamics or from analytical PES. Even for small-size systems, the use of an analytical surface may be a convenient choice. GAfit is a genetic algorithm-based software which can parameterize PES in an easier way. It needs the atom-atom distances for a particular orientation and the energy value. The software can fit them simultaneously and provide generalized atom-atom potential in form of Buckingham, modified Buckingham, Lennard-Jones, or any other functional form. This is indeed a very powerful tool to parameterize PES for dynamics of larger system as well as system that is unstable in direct dynamics. In our group, we develop very accurate force field parameters required for our dynamics.

Publications:

Complete List of Publications:

2024

55. A. Agarwal, A. K. Paul*, Exploring the Competition between Energy Transfer and Reaction Rate in Post-TS Dynamics of Catechol's Ozonolysis, Chapter in SPRINGER NATURE book series “Progress in Theoretical Chemistry and Physics." (QSCP XXVI proceedings)

54. A. Das, S. Dey, R. N. Yadav, P. Dutta, S. Dhiman, P. Boruah, K. Sarkar, A. Sahu, A. Jana, A. K. Paul, and M. F. Hossain, Unleashing Naphthopyranopyrimidine's Anticancer Potential: A Deep Eutectic Solvent (DES) Study, Accepted in New J. Chem.

53. P. J. Boruah, M. Debnath, A. Agarwal, G. Kalita, P. N. Chatterjee, and A. K. Paul, A Theoretical Investigation to Understand the Difference in Reactivities of Secondary and Tertiary Propargylic Alcohols with 1,3,5-Trimethoxybenzene in Presence of Brnøsted Acid, Int J Chem Kinet. 2024;1-12. https://doi.org/10.1002/kin.21714

52. P. J. Boruah, Venkatesh N, A. Samanta, A. K. Paul, A Detailed Theoretical Investigation on Intramolecular Charge Transfer Mechanism of Primary, Secondary, and Tertiary p-amino Substituted Benzaldehyde, Chem. Phys. Impact 8, 100538 (2024) (Special Issue: Recent Trends of Physical Chemistry in India)

51. A. Agarwal and A. K. Paul*, Details of Exit Channel Dynamics of the Ozonolysis of Catechol in Condensed Phase: Product Channels and Product Energy Partitioning, Chem. Phys. Impact, 8, 100440 (2024)

50. B. Deb, H. Mahanta, N. P. Baruah, M. Khardewsaw, and A. K. Paul, On the Intramolecular Vibrational Energy Redistribution Dynamics of Aromatic Complexes: A Comparative Study on C6H6 - C6H5Cl, C6H6 - C6H3Cl3, C6H6 - C6Cl6 and C6H6 - C6H5F, C6H6 - C6H3F3, C6H6 - C6F6. J. Chem. Phys.* 160, 024307 (2024)

2023

49. Ankita Agarwal, Shrutimala Baruah, Samir Ahmed, Palash Boruah, and A. K. Paul*, Post Transition State Direct Dynamics Simulations on the Ozonolysis of Catechol in N2 bath and comparison with gas phase dynamics J. Phys. Chem. A. 127, 6404 (2023)

48. Basudha Deb, S R Ngamwal Anal, Himashree Mahanta, Yogita, and A. K. Paul*, Unimolecular Dissociation of C6H6-C6H5Cl, C6H6-C6H3Cl3, and C6H6-C6Cl6 Complexes using Machine Learning Approach, J. Chem. Phys. 158, 194104 (2023)

47. Ankita Agarwal, A. K. Paul, Details of Ozonolysis of Catechol at High Temperature and Product Energy Distribution, J. Chem. Sci.* (2023)135:33

46. Arindam Das, Sovan Dey, Ram Naresh Yadav, Palash Jyoti Boruah, Prerana Bakli, Sourav Sarkar, Partha Mahata, A. K. Paul, Md. Firoj Hossain, An Expeditious One-Pot Two-Component Synthesis of Quinoxaline Derivatives in Natural Deep Eutectic Solvents (NADESs) , Chem.Selec. 8, e202204651 (2023)

45. Sovan Dey, Arindam Das, Ram Naresh Yadav, Palash Jyoti Boruah, Prerana Bakli, Tania Baishya, Koushik Sarkar, Anup Barman, Ranabir Sahu, Biplab Maji, A. K. Paul, Md. Firoj Hossain, Visible Light-Induced Ternary Electron Donor-Acceptor Enabled Synthesis of 2-(2-Hydrazinyl) thiazole Derivatives and The Assessment of Their Antioxidant and Antidiabetic Therapeutic Potential, Org. Biomol. Chem. 2023, 21, 1771-1779

2022

44. S. S. Ahamed, H. Mahanta, A. K. Paul*, An Advanced Bath Model to Simulate Association Followed by Ensuing Dissociation Dynamics of Benzene + Benzene System: A Comparative Study of Gas and Condensed Phase Results, Accepted in PCCP.

43. A. Agarwal, P. J. Boruah, B. Sarkar, and A. K. Paul, Post Transition State Direct Dynamics Simulations on the Ozonolysis of Catechol. J. Phys. Chem. A* 2022, 126, 32, 5314–5327

42. S. Kumar, S. Kumari, S. Singh, P. J. Boruah, A. K. Paul, P. Roy, and H. Joshi, Oxidized Charcoal-Supported Thiol-Protected Palladium Nanoparticles for Cross Dehydrogenative Coupling of Heteroarenes. ACS Appl. Nano Mater. 2022, 5, 2, 2644–2654.

2021

41. H. Mahanta, A. K. Paul, Dynamical Behavior of Aromatic Trimer Complexes in Unimolecular Dissociation Reaction at High Temperatures. Case Studies on C6H6-C6F6-C6H6 and C6H6-trimer Complexes. J. Phys. Chem. A* 2022, 126, 2, 259–271 (Accepted in 2021, published in 2022).

40. Shyamal Kanti Bera, Palash J. Boruah, Shraddha Saraswati Parida, Amit K. Paul* and Prasenjit Mal*, A Photochemical Intramolecular C-N Coupling Towards the Synthesis of Benzimidazole- Fused Phenanthridines. J. Org. Chem. 2021, 86, 14, 9587–9602

2020

38. S. S. Ahamed, P. Kumar, H. Kalita, A. K. Paul, Mode-to-Mode Collision Energy Transfer from Vibrationally Excited C6F6 to NO/N2 Mixed Bath with the Development of New Potential Energy Functions, Chem. Select.* 5, 10475-10487 (2020). https://doi.org/10.1002/slct.202002600
37. H. Mahanta, Sumadevi N., R. Mishra, A. K. Paul, Unimolecular Dissociation Dynamics of C6H6-C6Cl6 Complex and The Effect of Anharmonicity, Int. J. Mass. Spectro.* 456, 116392 (2020). https://doi.org/10.1016/j.ijms.2020.116392
36. S. S. Ahamed, H. Kim, A. K. Paul, N. A. West, J. D. Winner, D. A. Donzis, S. W. North, and W. L. Hase, Comparison of Intermolecular Energy Transfer from Vibrationally Excited Benzene in Mixed Nitrogen-Benzene Baths at 140 and 300 K. J. Chem. Phys.* 153, 144116 (2020). https://aip.scitation.org/doi/10.1063/5.0021293
2019
35. S. S. Ahamed, H. Mahanta, A. K. Paul, A Competition Between Dissociation Pathway and Energy Transfer Pathway: Unimolecular Dissociation of Benzene-Hexafluorobenzene Complex in Nitrogen Bath. J. Phys. Chem. A 123, 10663–10675 (2019) https://pubs.acs.org/doi/10.1021/acs.jpca.9b07258
34. S. S. Ahamed, H. Mahanta, A. K. Paul, Unimolecular dissociation of C6H6-C6F6 complex in N2 bath and comparison with gas phase dynamics. Chem. Phys. Letts. 730, 630-633 (2019) https://doi.org/10.1016/j.cplett.2019.06.063.
33. H. Mahanta, D. Baishya, Sk. S. Ahamed, and A. K. Paul, Chemical Dynamics Simulations on Association and Ensuing Dissociation of Benzene-Hexafluorobenzene Molecular System, J. Phys. Chem. A 123, 5019-5026 (2019). https://pubs.acs.org/doi/10.1021/acs.jpca.9b02332.
32. H. Mahanta, D. Baishya, Sk. S. Ahamed, and A. K. Paul. A Better Understanding of the Unimolecular Dissociation Dynamics of Weakly Bound Aromatic Compounds at High Temperature: A Study on C6H6-C6F6 and Comparison with C6H6 Dimer. J. Phys. Chem. A 123, 2517-2526 (2019). https://pubs.acs.org/doi/10.1021/acs.jpca.8b12188.
2018
31. A. K. Paul, N. A. West, J. D. Winner, R. D. W. Bowersox, S. W. North, and W. L. Hase. Non-statistical intermolecular energy transfer from vibrationally excited benzene in a mixed nitrogen-benzene bath. J. Chem. Phys. 149, 134101 (2018). https://aip.scitation.org/doi/10.1063/1.5043139
30. H. N. Bhandar, X. Ma, A. K. Paul, P. Smith, and W. L. Hase. PSO Method for Fitting Analytic Potential Energy Functions. Application to I–(H2O). J. Chem. Theory Comput., 2018, 14 (3), pp 1321–1332. https://pubs.acs.org/doi/abs/10.1021/acs.jctc.7b01122
29. N. K. Nath, M. Hazarika, P. Gupta, N. R. Ray, A. K. Paul, E. Nauha. Plastically bendable crystals of probenecid and its cocrystal with 4,4?-Bipyridine. J. Mol. Str. Vol. 1160, Pages 20-25, Year 2018. https://www.sciencedirect.com/science/article/pii/S0022286018300735
2017
28. A. K. Paul, D. Donzis, W. L. Hase, Collisional Intermolecular Energy Transfer from a N2 Bath at Room Temperature to a Vibrationlly “Cold” C6F6 Molecule Using Chemical Dynamics Simulations, Journal of Physical Chemistry A, Vol.-121, Issue No.-21, Page Nos - 4049-4057, Year 2017. http://pubs.acs.org/doi/abs/10.1021/acs.jpca.7b00948
2016
27. A. K. Paul and W. L. Hase, A Zero Point Energy Constraint for Unimolecular Dissociation Reactions. Giving Trajectories Multiple Chances to Dissociate Correctly, J Phys. Chem. A., Vol.-120, Page Nos -372, 2016.
26. H. Kim, A. K. Paul, S. Pratihar, and W. L. Hase, Molecular Dynamics Simulation of Intermolecular Energy Transfer : Azulene + N2 Collision, J Phys. Chem. A., Vol.-120, Page Nos -5187, 2016. http://pubs.acs.org/doi/abs/10.1021/acs.jpca.6b00893
2015
25. S. Kolakkandy, A. K. Paul, S. Pratihar, G. Barnes, and W. L. Hase, Energy and Temperature Dependent Dissociation of the Na+(Benzene)1,2 Complexes, J. Chem. Phys., Vol.-142, Page Nos -044306, 2015.
24. R. Sun, G. Granucci, A. K. Paul, M. Siebert, H. Liang, G. Cheong, W. L. Hase, and M. Persico, Potential Energy Surfaces for the HBr+ 2?3/2 and 2?1/2 Spin-Orbit States, J. Chem. Phys., Vol.-142, Page Nos -104302, 2015.
23. A. K. Paul, S. Kohale and W. L. Hase, Bath Model for N2 + C6F6 Gas-Phase Collision: Detail of Intermolecular Energy Transfer Dynamics, J. Phys. Chem. C, Vol.-119, Page Nos -14683, 2015.
22. A. K. Paul, S. Kolakkandy, and W. L. Hase, Dynamics of Na+(Benzene) + Benzene Association and Ensuing Na+(Benzene)2 Dissociation, J. Phys. Chem. A, Vol.-119, Page Nos -7894, 2015.
21. X. Ma, A. K. Paul, W. L. Hase, Chemical Dynamics Simulation of Benzene Dimer Dissociation, J Phys. Chem. A., Vol.-119, Page Nos -6631, 2015.
2014
20. A. K. Paul, S. C. Kohale, S. Pratihar, R. Sun, S. W. North, and W. L. Hase, A Unified Model for Simulating Liquid and Gas Phase Intermolecular Energy Transfer. N2 + C6F6 Collisions, J. Chem Phys., Vol.-140, Page Nos -194103, 2014.
2013
19. A. K. Paul, S. Kolakkandy, S. Pratihar, and W. L. Hase, Computation of Intrinsic RRKM and Non-RRKM Unimolecular Rate Constants. Chapter 20 of the book titled: "Reaction Rate Constant Computation: Theory and Computation", Pub: Royal Society of Chemistry, Eds: Keli Han, and Tianshu Chu, p. 494 (2013).
18. S. Sardar, S. Mukherjee, A. K. Paul, and S. Adhikari, Conical intersections between X2A1 and A2B2 electronic states of NO2, Chem. Phys., Vol.-416, Page Nos -11, 2013.
17. S. Mukherjee, S. Bandyopadhyay, A. K. Paul and S. Adhikari, Construction of Diabatic Hamiltonian Matrix from ab Initio Calculated Molecular Symmetry Adapted Nonadiabatic Coupling Terms and Nuclear Dynamics for the Excited States of Na3 Cluster, J. Phys. Chem. A, Vol.-117, Page Nos -3475, 2013.
16. M. Paranjothy, R. Sun, A. K. Paul, and W. L. Hase, Models for Intrinsic Non-RRKM Dynamics. Decomposition of the SN2 Intermediate Cl––CH3Br, Z. Phys. Chem., Vol.-227, Page Nos -1361, 2013.
15. S. Mukherjee, S. Bandyopadhyay, A. K. Paul and S. Adhikari, The molecular symmetry adapted non - adiabatic coupling terms and diabatic Hamiltonian matrix, Journal of Physics: Conference Series, Vol.-428, Page Nos -012008, 2013.
2012
14. A. K. Paul, S. Ray and S. Adhikari, Adiabatic to Diabatic transformation and nuclear dynamics on diabatic Hamiltonian constructed by using ab initio potential energy surfaces and non - adiabatic coupling terms for excited states of Sodium trimer, Chapter in Proceedings of JT 2010, Pub: Springer, Eds: M. Atanasom and C. Dual. p. 281 (2012).
2011
13. S. Sardar, A. K. Paul, R. Sharma, and S. Adhikari, A classical trajectory driven nuclear dynamics by a parallelized quantum classical approach to a realistic model Hamiltonian of benzene radical cation, Int. J. Quan. Chem., Vol.-111, Page Nos -2741, 2011.
12. A. K. Paul, S. Ray, D. Mukhopadhyay and S. Adhikari, Conical intersections in 22E’ states of Na3 cluster, Chem. Phys. Letts., Vol.-508, Page Nos -300, 2011.
11. A. K. Paul, S. Ray, D. Mukhopadhyay and S. Adhikari, Ab initio calculations on the excited states of Na3 cluster to explore beyond Born – Oppenheimer theories: Adiabatic to diabatic PESs and nuclear dynamics, J. Chem. Phys., Vol.-135, Page Nos -034107, 2011.
2010
10. A. K. Paul, B. Sarkar and S. Adhikari, Single surface beyond Born - Oppenheimer equation for the excited states of Sodium trimer, Chapter in Recent Advances in Spectroscopy, Pub: Springer Verlag, Eds: Chaudhuri, R. K.; Mekkaden, M.V.; Raveendran, A.V.; Satya Narayanan, A. (2010) p. 63.
9. S. Sardar, A. K. Paul and S. Adhikari, A quantum-classical simulation of the nuclear dynamics in NO2- and C6H6+with realistic model Hamiltonian, J. Chem. Sci. 122, 491 (2010).
8. A. K. Paul, S. Adhikari, R. Baer and M. Baer, H2+ photodissociation by a intense pulsed photonic Fock state, Phys. Rev. A, Vol.-81, Page Nos -013412, 2010.
7. A. K. Paul, S. Adhikari, and M. Baer, Space - Time contours to treat intense field - dressed molecular states, J. Chem. Phys, Vol.-132, Page Nos -034303, 2010.
6. A. K. Paul, S. Adhikari and M. Baer, A treatise on the interaction of molecular system with short – pulse highly – intense external fields, Phys. Rep., Vol.-496, Page Nos -79, 2010.
2009
5. S. Sardar, A. K. Paul, R. Sharma and S. Adhikari, The multi state multi mode vibronic dynamics of benzene radical cation with a realistic model Hamiltonian using a parallelized algorithm of quantum classical approach, J. Chem. Phys., Vol.-130, Page Nos -144302, 2009. http://scitation.aip.org/content/aip/journal/jcp/130/14/10.1063/1.3108488
4. S. Sardar, A. K. Paul and S. Adhikari, A Quantum - Classical approach to explore the photo absorption spectrum of allene radical cation, Mol. Phys., Vol.-107, Page Nos -2467, 2009. http://www.tandfonline.com/doi/abs/10.1080/00268970903362326#.V5XnCEZ97IU
3. A. K. Paul, S. Adhikari, Debasis Mukhopadhyay, G. J. Halász, ´ A. Vibók, Roi Baer and Michael Baer, Photodissociation of H2+ upon exposure to an intense pulsed photonic Fock state, J. Phys. Chem. A, Vol.-113, Page Nos -7331, 2009. http://pubs.acs.org/doi/abs/10.1021/jp811269g?journalCode=jpcafh
2. A. K. Paul, S. Sardar, B. Sarkar and S. Adhikari, Single surface beyond Born - Oppenheimer equation for a three state model Hamiltonian of Na3 cluster, J. Chem. Phys., Vol.-131, Page Nos -124312, 2009.
2008
1. S. Sardar, A. K. Paul, P. Mondal, B. Sarkar and S. Adhikari, A quantum - classical approach to the molecular dynamics of butatriene cation with a realistic model Hamiltonian, Phys. Chem. Chem. Phys, Vol.-10, Page Nos - 6388, 2008.
http://pubs.rsc.org/en/content/articlelanding/2008/cp/b805990j#!divAbstract

Recognition:

Qualified the Graduate Aptitude Test in Engineering, 2007
Qualified the National Eligibility Test under CSIR fellowship (JRF), 2007
Selected for OCES-2007 (IGCAR) at BARC, Mumbai, 2007
International travel reward (including TA, DA and accommodation) from XXIst International Symposium on the Jahn-Teller Effect, 2012
Popular Poster award at XXIst International Symposium on the Jahn-Teller Effect, 2012
Visiting Scholar, University of Pisa, Italy, 2014
Guided the Best Masters’ thesis of NIT Meghalaya for the year 2022, 2022
Member of Editorial Board, International Journal of Chemical Kinetics, 2023
Guided the best Masters’ thesis award of NIT Meghalaya for the year 2023, 2023

Teaching:

Courses Taught in NIT Meghalaya (Previous Employer)

M.Sc

Quantum Mechanics (CY407), Autumn Semester, 2016-2022.
Symmetry Group Theory (CY 406), Spring Semester, 2016-2022.
Molecular Spectroscopy (CY 408), Spring Semester, 2016-2022.
Chemical Kinetics (CY 531), Autumn Semester, 2016-2022.
Computational Chemistry (CY 536), Spring Semester, 2016-2022.
Analytical Chemistry (CH701), Autumn Semester, 2023

B.Tech

Environmental Science (CY 102), Spring Semester, 2016-2022.

PhD

Analytical Techniques (CH 701), Autumn Semester, 2016-2022.

Students:

Image	Name	Designation	Department	Campus	Contact number	Email

Former:

Check out our Research Group Webpage

Present Group Members (All are Affiliated to NIT Meghalaya)

Mr. Palash Jyoti Baruah, M.Sc.

E-mail: palashjyoti36@gmail.com

Phone No.: 8638405615

Working for his Ph.D. since July 2019

Research Area: Electronic Structure calculations and Non-adiabatic dynamics

Ms. Basudha Deb, M.Sc.

E-mail: p22cy006@nitm.ac.in

Phone No.: 8473043722

Working for her Ph.D. since July 2022

Research Area: Gas phase reaction dynamics of aromatic complexes

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Ms. Manju Yadav, M.Sc.

E-mail: p22cy007@nitm.ac.in

Phone No.: 9730442407

Working for her Ph.D. since July 2022

Research Area: Energy transfer and reaction dynamics in condensed-phase molecular systems

Mr. Krishnandu Dey, M.Sc.

E-mail: p23cy001@nitm.ac.in

Phone No.: 8402815130

Working for his Ph.D. since January 2023

Research Area : Non-adiabatic dynamics in photoswitchable organic molecules.

Mr. Baristar Lynkhoi, M.Sc. (Part-time)

E-mail: p22cy009@nitm.ac.in

Phone No.: 8787505388

Working for his Ph.D. since July 2022

Group Alumni

Dr. Himashree Mahanta

Received Degree on 23/05/2022

Thesis Title: The Understanding of the Intramolecular Interactions in Aromatic Complexes through Computational Investigations of Unimolecular Dissociation and Association Reactions

Current Position: Assistant Professor, Department of Chemistry, Kaziranga University

Dr. Sk. Samir Ahamed

Received Degree on 05/09/2022

Thesis Title: Molecular Dynamics Simulation on Energy Transfer and Chemical Reactions in Single/Mixed Bath Molecular Systems

Current Position: Post Doctoral Research Associate at SNBNCBS, Kolkata

Dr. Ankita Agarwal

Received Degree on 21/05/2024

Thesis Title: Post-Transition State Dynamics on Ozonolysis of Catechol in Gas and Condensed Phase

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Amit Kumar Paul Associate Professor

Amit Kumar Paul Associate Professor, Chemical Sciences