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Obituary: Frank H. Clarke

by Nina Notman, special to C&EN
March 12, 2023 | A version of this story appeared in Volume 101, Issue 9


Frank H. Clarke
Credit: Moses K. Kaloustian
Frank H. Clarke

Frank H. Clarke, 95, died Jan. 15, 2023 in Califon, New Jersey.

“Frank was a modern Renaissance man: chemist, X-ray crystallographer, artist, inventor, programmer, author, raconteur, and historian.

Under G. Stork’s doctoral mentorship at Harvard University, Frank completed the total synthesis of cedrene and cedrol. During his postdoctoral studies at Columbia University, he established the correct structures of α-halocodides and studied their SN2’ reactions.  Subsequently, he became senior research scientist at Schering, director of medicinal research at Geigy, and distinguished senior research fellow at Ciba-Geigy.

He authored a number of books, edited IUPAC’s “Strategy of Drug Research,” and served as editor in chief of Annual Reports in Medicinal Chemistry (vol. 11).  He also chaired the organic division of the New York Academy of Sciences.

At ChemClarke, in Califon, he invented the Clarke titrator, an automated potentiometric instrument for the measurement of pKa values of potential drugs. He also invented the molecular model assembly, a set of skeletal-space-filling molecular models for the visualization of large biomolecules and active sites of enzymes.

As an artist, he filled his home with his masterful, colorful, and joyful paintings and drawings.

Frank had an unforgettable hearty laughter. He was the perfect example of a wonderful, kind, modest, and sweet human being.  He was Ginny’s devoted husband for nearly 7 decades, a superb dad, and a loving grandfather.”—Moses K. Kaloustian

Most recent title: Distinguished senior research fellow, Ciba-Geigy

Education: BS, chemistry, 1948, and MS, chemistry, 1950, University of New Brunswick; PhD, organic chemistry, Harvard University, 1955

Survivors: Wife, Ginny; daughters, Susan and Sarah; four grandchildren

To recognize your late loved one or colleague, submit obituary information at


This article was updated on March 15, 2023, to correct the degrees earned. The BS and MS were in chemistry, not medicinal research.

This article was updated on March 14, 2023, to correct the writer of the obituary remembrance. It is Moses K. Kaloustian, not Bernadette Taylor. And the credit for the photo is Moses K. Kaloustian, not courtesy of Bernadette Taylor.


This obituary was updated on March 14, 2023, to provide more details about Frank H. Clarke’s life, including the compounds he worked with, his involvement in the organic division of the New York Academy of Sciences, his employment history, and his interest in art. The new text also clarifies that his inventions of a potentiometric instrument and skeletal-space-filling molecular models occurred at ChemClarke.


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