[1] Francl is noted for developing new methodology in computational chemistry, including the 6-31G* basis set for Na to Ar and electrostatic potential charges.
On a list of the 1000 most cited chemists,[2] Francl is a member of the editorial board for the Journal of Molecular Graphics and Modelling, active in the American Chemical Society and the author of The Survival Guide for Physical Chemistry.
[5][6] In April 2016, Francl was named one of nine adjunct scholars of the Vatican Observatory also known as (Italian: Specola Vaticana).
Francl was awarded the 2019 American Chemical Society's Philadelphia Section Award which recognizes an individual, "who, by conspicuous scientific achievement through research, has made important contributions to man's knowledge and thereby aided the public appreciation of the profession.
[8][9][10] Francl has subsequently noted that eating some fruits and vegetables can impact the duration of time that caffeine remains in the body.