Bio

Professor Heather C. Allen attended Saddleback College from 1989-1992, completing much of her undergraduate science and general education coursework before transferring to the University of California, Irvine in 1992.  After her second year at Saddleback, she focused on the sciences, targeting chemistry as her major, winning a Saddleback College Science Scholarship Award to continue advancement toward her chemistry degree.  She received her B.S. degree in Chemistry in 1993, and Ph.D. in Physical Chemistry in 1997 at the University of California Irvine working with Nobel Laureate Sherwood Rowland and Don Blake as an undergraduate, and as a graduate student with John Hemminger and Barbara Finlayson-Pitts. She continued her postdoctoral studies in 1997 at the University of Oregon advised by Geraldine Richmond. Following the Saddleback Science Scholarship, as a student and postdoctoral researcher, she was also recognized with and by the Fannie and John Hertz Fellowship, EPA, NSF Traineeship, and a NOAA Post-Doctoral Fellowship in Climate and Global Change. 

Dr. Allen began her professorial career at Ohio State University in 2000, and has since been recognized for many research accomplishments, most recently the 2022 American Chemical Society Irving Langmuir Award in Chemical Physics for her cumulative work on liquids. Her prior awards include the Ohio State Distinguished Scholar Award, the Alexander von Humboldt Research Award from Germany, Alfred P. Sloan Research Fellow Award, Camille Dreyfus Teacher-Scholar Award, Fellow of the American Association for the Advancement of Science (AAAS), Research Innovation Award from Research Corp., NSF CAREER Award, and a Beckman Young Investigator Award.

Dr. Allen also has been recognized for several mentoring awards including the American Chemical Society National Award for Encouraging Women into Careers in the Chemical Sciences, an Empowered Woman Award from the City of Columbus, and an Ohio State Office of Minority Affairs Mentor Award.  She is a Full Professor in the Department of Chemistry and Biochemistry, and in the Department of Pathology.  

Research Overview

Dr. Allen’s research specialization is in interfacial phenomena, molecular organization, ions, ion pairing, and hydration at aqueous interfaces. Investigations of molecular organization and orientation, and chemical reaction mechanisms at gas - liquid, gas - solid, and liquid - solid interfaces are of interest. Laboratory experiments are designed to further understand organization of solvated ions and molecules such as water, lipids, and fatty acids and complexation at liquid surfaces and interfaces of biological and environmental relevance.

The Allen group utilizes and designs optical spectroscopic instruments and studies liquids and “soft” surfaces to understand fundamental processes. Applications range from ocean and atmospheric aerosol chemistry, thundercloud electrification, geochemistry, cell membrane organization, and lung lining surfactant systems. 

Dr. Allen was first to design the broadband vibrational sum frequency generation (BB-VSFG) system specifically for use on liquid surfaces. (Anal. Sci. 2001, 17(11), 1325-1329; and Anal. Sci. 2001, 17(1), 137-139.) BB-VSFG, since simplified to one femtosecond amplifier, is now common-place in VSFG laboratories. VSFG is inherently interface-selective and provides molecular-level interfacial information that includes relative orientation and structure of the surface species, i.e. the surface signature. 

In addition to VSFG, an array of analytical optical spectroscopic and interfacial tools is incorporated to fully understand the heterogeneous chemical processes at an interface. The Allen lab also has expertise in and uses Second Harmonic Generation, Polarized Raman Spectroscopy, Infrared Reflection Spectroscopies, Brewster Angle Microscopy and Surface Potential and Surface Tension Instrumentation. 

Previous Allen group members have positions in industry, national laboratories, and academia: Battelle Corporation, Intel, American Regent, Procter and Gamble, Spartan Chemical, OSU Surface Science Facility, Syngenta, Nestle, PPG Technologies, KLA Tencor, Chemical Abstracts Service, Canadian Synchrotron Facility, United States Geological Survey (USGS), Naval Research Lab (NRL), Pacific Northwest National Laboratory (PNNL), National Center for Atmospheric Research (NCAR), and professor positions at Hebei University in Baoding, China, Ohio Wesleyan University, and University of Findlay.

Publications

A complete list of Allen Group's publications is available.

(Selected Publications)

Visualization of Monolayer Restructuring at the Air-Aqueous Electrolyte Interface Revealed by Brewster Angle Microscopy: Biological, Atmospheric, and Environmental Perspectives, Narendra Adhikari & Heather C. Allen, invitation for Volume 20 of the Annual Review of Analytical Chemistry , 07.08.2026

Inner Sphere Fe-OSO3 Coordination, Iron (III) and Sulfate Hydration in Aqueous Solutions Observed by Polarized Raman Spectroscopy, Gwen Nieto, Biswajit Biswas, Heather C. Allen, submitted to PCCP 6.25.2026

Amphiphilic Baskets for Supramolecular Nanoarchitectures at Interfaces: Inverted Monolayer Formation on Water, Tai Bowling-Charles, Nitesh Kumar*, Sefa Ucar, Carson E. Ward, Shamma Jabeen Proma, Jovica Badjić, Heather C. Allen*, Accepted/in press 5.19.26 in Langmuir (funded by NSF Bridge & DOE)

Surface Potential of Phospholipid Monolayer Membranes Revealed by Phase-Sensitive Second Harmonic Generation, Narendra M. Adhikari, Biswajit Biswas, Colin Bang, and Heather C. Allen*, resubmitted 07.26 to JCIS funded by DOE BES CPIMS)

IR Spectroscopy and Linear Support Vector Machine Analysis of Colorectal Liver Metastasis, James V. Coe*, Heather C. Allen, Samantha A. Skarda, Trina D. Orr, Antrae L. Wilson II, Destiny G. Wilson, Susan Kalliantas, Steven V. Nystrom, Rebecca C. Bradley, Ran Li, Zhaomin Chen, Charles. L. Hitchcock, and Edward W. Martin Jr., J. Phys. Chem. B 2026, 130, 6, 1798–1809 (funded by NCI, NIH & IR Medtek LLC) Open Access

Linear Support Vector Machine Model of an IR Spectral Library:  Application to Skin Cancer, Bradley, Rebecca; Erwin, Justin; Obersyszyn, Tatiana; Tober, Kathleen; Hitchcock, Charles; Allen, Heather; Coe, James*;  ACS Omega 2025, 10, 51, 63573–63582 (IF 4.3) Open Access

Reorganization of Water at Aqueous Aluminum Chloride (AlCl3) Interfaces: Vibrational Sum Frequency Generation and Molecular Dynamic Simulation; Biswajit Biswas, Mohammadhasan Dinpajooh*, Gwendolyn Nieto, Narendra Adhikari, Gregory K. Schenter, Shawn M. Kathmann, Christopher J. Mundy, Heather C. Allen*, J. Phys. Chem. A 2025, 129, 46, 10616–10631 (IF 2.8)  https://doi.org/10.1021/acs.jpca.5c03910  (funded by DOE BES CPIMS)

Nanoplastic–Lipid Interactions at Marine Relevant Interfaces: Implications for Atmospheric Chemistry; S. J. Proma, B. Biswas, S. Sujon, K. Moor, J. Brahney, H. C. Allen*; Environmental Science: Atmospheres (IF 3.5 ), 2025, DOI: 10.1039/D5EA00075K; (funded by Herbert Hoover Foundation) Open Access,