Prof. dr hab. Krystyna Rotkiewicz passed away after a long illness on December 21, 2019 at the age of 83. For over four decades, since 1968 until retirement, she worked at the Photochemistry and Spectroscopy Department of the Institute of Physical Chemistry (IPC) of the Polish Academy of Sciences.
Krystyna Rotkiewicz graduated as a chemist from the Warsaw University of Technology in 1959. A few years later, she started her PhD studies under the guidance of prof. Zbigniew R. Grabowski. Her most important professional achievements are linked to IPC: habilitation in 1990 and, 11 years later, obtaining the title of chemistry professor from President Aleksander Kwaśniewski. Earlier on, upon request of the Minister of National Education, she was awarded by the same president with the Silver Cross of Merit.
She considered prof. Zbigniew R. Grabowski, prof. Albert Weller, and dr Karl-Heinz Grellman her most important tutors. With the first of them, she was also tied by bonds of friendship. In his autobiography book, entitled In the corroded mirror of memory, prof. Grabowski mentions Krystyna as his "most faithful coworker". He writes: "We entered the extremely interesting area of intramolecular charge separation thanks to Krystyna Rotkiewicz, who, at the beginning of the 70's got interested in a compound usually abbreviated as DMABN". Their work (including several more scientists) resulted, i.a., in the introduction into the literature of the acronym currently well-known and very often used: TICT (twisted intramolecular charge transfer). The publication from 2003: Structural Changes Accompanying Intramolecular Electron Transfer:  Focus on Twisted Intramolecular Charge-Transfer States and Structures by prof. Grabowski, Krystyna Rotkiewicz, and prof. Wolfgang Rettig became one of the most quoted paper written by scientists from IPC (ca. 2500 times at the end of 2019).
Since 1994 until retirement, Krystyna Rotkiewicz was also tied to the High Pedagogical School in Kielce, later transformed into Świętokrzyska Academy, and then into Jan Kochanowski University in Kielce. There, she was professor and Head of Chemical Physics Department.
Krystyna Rotkiewicz was not only a scientist, but also a social activist. In the 70's, she collaborated with Workers' Defense Committee, and since 1980 she belonged to Solidarity Trade Union. She was elected president of the company branch of Solidarity at IPC in 1991-1994.
In the memory of those who had the opportunity to meet her, she will always remain as a cheerful, serene, and good-hearted, always smiling person.