Professor Anna Krylov Inducted into American Academy of Arts and Sciences

The American Academy of Arts and Sciences is one of the nation’s oldest scholarly institutions dedicated to honoring excellence and bringing together leaders from many fields of study to examine new ideas, address matters of importance to the US and the world, and to work together for the advancement of society. Anna Krylov, USC Associates Chair in Natural Sciences and Professor of Chemistry, has recently been inducted as a member, a prestigious recognition of her influential work in the field of theoretical chemistry. The election process involves nomination by current members and a thorough review of the nominee’s contributions to the arts and sciences. Prof. Krylov is now one of three faculty members in the Department of Chemistry to hold this distinction, joining the late George Andrew Olah (elected in 2002) and Hanna Reisler (elected in 2021).

Founding a Lab for Open Shell and Electronically Excited Molecules

Since founding her lab, iOpenShell, in 1998, Krylov has been a pioneering force in the field of theoretical and computational chemistry. The lab focuses on understanding the electronic structure and spectroscopy of electronically excited and open-shell species—types of molecules that are difficult to study using traditional quantum-chemistry methods. These include radicals, molecules with transition metals, and highly energetic species, such as molecules excited by light or by electrons. The lab develops theoretical frameworks and computational tools to analyze these species, helping researchers to understand phenomena that are central to spectroscopy, bioimaging, catalysis, energy research, and many technological innovations. Krylov’s research provides solutions to long-standing problems of strong correlation and metastable states as well as spectroscopy modeling in non-linear and high-energy regimes. Her work is highly cited and continues to influence the field of quantum chemistry.

Developing a Computational Tool with Broad Reach

As President of Q-Chem, Inc., Anna Krylov leads the development of Q-Chem, a comprehensive ab initio quantum chemistry software package. Q-Chem software is developed and used by a large network of global researchers to solve complex computational problems. It allows scientists to run calculations on various molecular systems, yielding insights that guide their research. Over the years, Krylov and her group have contributed many important features to Q-Chem, such as tools for spectroscopy modeling and treatments for open-shell and electronically excited species.

At USC, Krylov teaches a popular graduate-level class that equips students with skills to deploy quantum chemistry software to aid their research. Beyond USC, Krylov is often delivering popular quantum chemistry tutorials and webinars. Additionally, the iOpenShell lab collaborates extensively with experimental groups, including the Reisler Group, the Bradforth Group, the Takahashi Group and the Zhang Group, providing computational expertise to help interpret results and guide future directions. According to Krylov, nearly one-third of her co-authored papers are the result of such collaborative efforts.

Discovering the Spin-Flip Approach

A major contribution of Krylov’s work is the development and application of the spin-flip (SF) approach, a powerful method used to describe and understand complex open-shell systems. In simple terms, this approach involves “flipping” the spin of one electron (from α to β or vice versa) in a molecule to reach “difficult to describe” electronic states, such as those emerging in bond breaking or systems with multiple unpaired electrons like diradicals or triradicals. This technique allows scientists to calculate these challenging states accurately and efficiently by using a high-spin reference state where electron correlation is easier to manage. The SF approach has become a popular tool in the field and is being used to develop future technologies, including molecular magnets, which have potential applications in quantum computing and lightweight electronics.

Contributions Beyond Chemistry

Krylov is an outspoken advocate of freedom of speech and academic freedom. She is a founding member of the Academic Freedom Alliance and a member of its academic leadership committee. At USC, she is serving on Academic Freedom Task Force. She was also recognized by Dornsife College of Letters, Arts, and Sciences with the inaugural Communicator of the Year Award.

Prof. Krylov has several highly influential publications. Her paper “The Peril of Politicizing Science,” which launched a national conversation among scientists and the general public on the growing influence of political ideology over STEM, has received over 100,000 views. Krylov’s writings have been translated into French, Polish, Russian, and Estonian. In her acceptance letter to the Academy, Krylov emphasized the role of the Academy in defending free inquiry from political attacks from both sides of the political spectrum and expressed optimism about the future of American universities.

A Well-Earned Recognition

Reflecting on her induction into the Academy, Anna Krylov explains, “I was very excited. I felt very honored to be elected. It’s also recognition of the field; it sends the message that fundamental quantum mechanical theory and ab initio methods continue to be important for chemistry.” She emphasizes that this honor is not hers alone: “It’s really a collective honor because it’s based on the bulk of work I carried out with the help of my past and present graduate students and post-docs. So, it’s recognizing their immense efforts as well.”