A5020627167- Spectroscopy and Quantum Chemical Studies
- Molecular Spectroscopy and Structure
- Advanced Chemical Physics Studies
- Isotope Analysis in Ecology
- Mass Spectrometry Techniques and Applications
- Inorganic Fluorides and Related Compounds
- Solid-state spectroscopy and crystallography
- Atmospheric Ozone and Climate
- Chemical and Physical Properties in Aqueous Solutions
- Molecular spectroscopy and chirality
- Advanced Chemical Sensor Technologies
- Crystallography and molecular interactions
- Quantum, superfluid, helium dynamics
- Marine and coastal ecosystems
National Institute of Science Education and Research
2020-2025
Homi Bhabha National Institute
2025
Yale University
2020-2023
Sterling Research Group
2020
University of New Haven
2020
In gas phase experiments [ J. Am. Soc. Mass Spectrom. , 2005, 16 2045], the reaction of CH 2 CN - ion with CCl 4 was observed to proceed predominantly via a halophilic reaction, where...
We report vibrational spectra of the H2-tagged, cryogenically cooled X- · HOCl (X = Cl, Br, and I) ion-molecule complexes analyze resulting band patterns with electronic structure calculations an anharmonic theoretical treatment nuclear motions on extended potential energy surfaces. The are formed by "ligand exchange" reactions (H2O)n clusters molecules at low pressure (∼10-2 mbar) in a radio frequency ion guide. generally feature many bands addition to fundamentals expected double harmonic...
The rates of many chemical reactions are accelerated when carried out in micron-sized droplets, but the molecular origin rate acceleration remains unclear. One example is condensation reaction 1,2-diaminobenzene with formic acid to yield benzimidazole. observed enhancements have been rationalized by invoking enhanced acidity at surface methanol solvent droplets low water content enable protonation generate a cationic species (protonated or PFA) formed attachment proton neutral acid. Because...
Decoding the structural information contained in interfacial vibrational spectrum of water requires understanding how spectral signatures individual molecules respond to their local hydrogen bonding environments. In this study, we isolated contributions for five classes sites that differ according number donor (D) and acceptor (A) bonds characterize each site. These patterns were measured by exploiting unique properties cluster cage structures formed gas phase upon hydration a series cations...
In the presence of a halide ion, hypohalous acids can adopt two binding motifs upon formation ion–molecule complexes [XHOY]− (X, Y = Cl, Br, I): hydrogen (HB) bond to acid OH group and halogen (XB) between anion halogen. Here we isolate X-bonded Cl–·IOH complex by collisions I–·(H2O)n clusters with HOCl vapor measure its vibrational spectrum IR photodissociation H2-tagged complex. Anharmonic analysis band pattern reveals that XB results in dramatic lowering HOI bending fundamental frequency...
Enhancement of the acid–base interaction between HNO<sub>3</sub> and water by a proximal Cs<sup>+</sup> cation with cryogenic ion vibrational spectroscopy.
We report the water-mediated charge separation of nitric acid upon incorporation into size-selected Cs+·(HNO3)(H2O)n=0–11 clusters at 20 K. Dramatic spectral changes are observed in n = 7–9 range that traced to formation many isomeric structures associated with intermediate transfer acidic proton water network. This is complete by 10, which exhibits much simpler vibrational band patterns consistent those expected for a tricoordinated hydronium ion (the Eigen motif) along NO stretching bands...
The speciation of strong acids like HNO3 under conditions restricted hydration is an important factor in the rates chemical reactions at air-water interface. Here, we explore trade-offs play when attached to alkali ions (Li+-Cs+) with four water molecules their primary shells. This achieved by analyzing vibrational spectra M+·(HNO3)(H2O)5 clusters cooled about 20 K a cryogenic photofragmentation mass spectrometer. local acidity acidic OH group estimated extent red shift its stretching...
We report the structural evolutions of water networks and solvatochromic response CH3NO2- radical anion in OH CH stretching regions by analysis vibrational spectra displayed cryogenically cooled CH3NO2-·(H2O)n=1-6 clusters. The bands evolve with a surprisingly large discontinuity at n = 6, which features emergence an intense, strongly red-shifted band along weaker feature that appears region assigned to free fundamental. Very similar behavior is perdeuterated carboxylate clusters,...