Dear Friends of Sihyun,

We are deeply saddened to share the news of the passing of Sihyun Ham, our friend, brilliant scientist, inspirational teacher, entrepreneur and leader in the fields of computational chemistry and biophysics. She passed away in Seoul on January 16, 2021, after a long battle with cancer that she had fought to the very end.  

Sihyun received her undergraduate degree in Chemistry at the Sookmyung Women's University in 1991, and her PhD degree at Texas Tech University in 1998 under the guidance of David Birney. She went on to be a postdoctoral researcher at the University of Washington in Seattle with Valerie Daggett. After another postdoc with Minhaeng Cho at Korea University, she returned to her Alma Mater Sookmyung Women's University as a Professor of Chemistry. In her independent career, she was a true force of nature for her unwavering advocacy of her Alma Mater and education for women, for the Korean Chemical Society and for tirelessly hosting international Computational Chemistry meetings in Korea and abroad.

Sihyun was well known and admired for her unyielding energy, determination and enthusiasm and for her humanitarian outreach for bettering lives by education. Even after her cancer diagnosis, known only to very few of her friends, she enthusiastically accepted a Visiting Professorship at the American University of Beirut between 2018-20 because she saw the impact of her hands-on teaching of computational chemistry to students with sparkling eyes and little access to state of the art research opportunities. Sihyun was also the inaugural organizer of the TSRC Workshop on Water Structure, Dynamics and Thermodynamics in Biology. Unfortunately, by the time this workshop took place in the summer of 2019, she was unable to travel to share her science with her fellow scientists that she had invited. 

Sihyun started her career as a computational chemist using electronic structure calculations to study the mechanisms of chemical reactions. She then moved on to push the boundaries for computational predictions of two-dimensional infrared spectroscopy signals for peptides and small proteins. In another change of research areas, she studied supramolecular host-guest systems using combined molecular dynamics simulations and electronic structure calculations. In her next transition, she entered the field of biomolecular solvation and became a leader at the forefront of combining conformational sampling via classical molecular dynamics with thermodynamic analysis of solvation using integral equation theory. Most recently, she has adapted these techniques to intrinsically disordered proteins and protein folding and introduced the solvent-averaged effective energy as a key parameter for protein conformational ensembles and their thermodynamic properties. 

Frequent transitions between research areas followed a clear plan in Sihyun's career. She purposefully switched gears every 5 years and explored a new research area to avoid becoming "too comfortable" in any of them. She mastered these transitions multiple times during her career and managed to establish herself as a leading expert in record time. The latter is not only a testament to her outstanding intellect and work ethic, but also to her unique ability to collaborate and network with a wide range of people from many distinct backgrounds. 

Sihyun managed to carry out brilliant research with initially very limited resources and always with only a few students, most closely with her long-term postdoctoral researcher and close collaborator Dr. Song-Ho Chong. As she demonstrated her skill and imagination, in 2014, she became one of a handful of scientists to receive a major five-year grant from the Samsung Future Technology Promotion Project to address the causes and solutions for incurable diseases caused by proteins. In the same year, she was named '2014 Female Scientist of the Year', awarded by the Ministry of Science, ICT and Future Planning and the National Research Foundation of Korea. Her creativity and impact led her to become the only researcher in the field of basic chemical sciences to be renewed for an additional five year Samsung grant in 2019, sadly, soon after she learned of her severe illness. While losing energy, she worked tirelessly on research ideas and papers until the last moments of her life, always hopeful, but knowing that little time was likely left for her to share her ideas and vision with the world. 

Sihyun was full of life, talent and dreams. She could stun her friends and colleagues in Chemistry with her amazing singing voice and captivated audiences with lively research talks that were accessible to the broader audience and educational for experts alike. You may get a small glimpse at Sihyun’s energy and presence in this ProWaVE video: https://www.youtube.com/watch?v=kxkqE4L8lL8

We lost our dear friend and cherished colleague too soon and regret that we could not see her scientific and educational dreams come completely to fruition. However, in memory of our special friend and fellow scientist, we encourage you to read her ingenious and original papers: http://ham.sookmyung.ac.kr/publications_all/

Songi Han

Matthias Heyden

Doug Tobias

John Straub

Peter Rossky