Welcome to the History Portal of the American Crystallographic Association 

Brian Toby’s commentary, “Crystallographic hallucinations,” presents several interesting conclusions from recent work on the structure of psilocybin (Sherwood, A. M., Kargbo, R. B., Kaylo, K. W., Cozzi, N. V., Meisenheimer, P. & Kaduk, J. A. (2022). Acta Cryst. C78, 36–55.). The results from single-crystal and powder diffraction agreed and were further validated by plane-wave density functional theory (DFT). Toby concludes, “powder diffraction crystallography can rise to the gold standard level that we expect from single-crystal analysis.” Another take-away from the research is the value of DFT for crystallographers. An interesting sidelight is the brief biography of Walter Kohn, who was rescued by the British during WWII and later immigrated to the US, where he won the Nobel Prize for DFT.

Maureen Julian presents an engaging view of Dame Kathleen Lonsdale’s crystallography group at University College London, complete with historical photographs. She followed up on the careers of the group members; it is interesting to see the variety of paths that each member of the lab followed. See "The laboratory of Dame Kathleen Lonsdale at University College London from 1966 to 1968 and then fifty years later.”

The prestigious Ewald Prize was awarded to Wayne Hendrickson in 2023 at the 26th IUCr Congress in Melbourne, Australia. The text of his lecture “Facing the Phase Problem” is now online. Also, see Janet Smith’s summary of his scientific career and achievements, "Commentary on `Facing the phase problem' by Wayne Hendrickson”.

Time-resolved X-ray spectroscopy on a picosecond or femtosecond scale makes it possible to study molecular rotation, isomerization, and vibration. Maged Chergui has been a pioneer in using pump-probe methods at synchrotrons to excite the molecule of interest and then follow its relaxation on ultrafast time scales, in order to learn about electronic structure, oxidation state, spin state, and local geometry. His David Rognlie Award Lecture is now online. He has applied these methods to study the protein dynamics of myoglobin, spin-crossover in iron(II) complexes, and molecular chirality in solution, demonstrating the broad applicability of the method.

In his Bau Award Lecture Arthur J. Schultz summarizes the history of neutron diffraction at Argonne National Laboratory, beginning with disassembling and moving the original graphite blocks from the first nuclear reactor at the University of Chicago. He describes the development of sources and detectors for single-crystal neutron diffraction, beginning with the proof of principle experiment in 1979. The applications have been very interesting, including Jahn-Teller switching in Tutton salts, organic superconductors, ferroelectrics, transition metal hydrides, and transition metal-hydrogen interactions.

Probably you are aware of the series “Molecule of the Month” by David Goodsell, featured on the RCSB-PDB website since 2000. In his 2022 Fankuchen Award lecture, “Art as a Tool for Structural Biology” he emphasizes the importance of visualization in structural science, for understanding, for communication, and for education and outreach. His long-term research work has been to develop a realistic model of a living cell, including the molecules present in greatest abundance in a way that enables researchers and students to see the structures that make life possible.