Open Problems Session
What are the most important unsolved problems in crystallography today?
At the 27th IUCr Congress and General Assembly (IUCr 2026), we are hosting a special Open Problem Session to highlight challenging questions that could inspire new ideas, collaborations, and breakthroughs across the crystallographic sciences.
We invite researchers from across the community to submit open problems—questions that remain unresolved, methods that still face limitations, structures that resist solution, or theoretical challenges that could shape the future of the field.
These problems may arise from experimental, computational, theoretical, or interdisciplinary work, and may span any area of crystallography.
This session will take place in the afternoon of August 13th (see schedule for full details).
Submit a Problem
Submissions should include:
Title of the Problem
Description of the Problem
Current State of Knowledge (references encouraged)
Significance of the Problem for the field
Keywords and relevant IUCr Commissions
Problems may relate to any area of crystallography, including (but not limited to):
Biological macromolecules
Materials crystallography
Electron crystallography
Powder diffraction
Quantum crystallography
Small-angle scattering
Crystallographic computing and theory
Synchrotron and XFEL science
Structural chemistry and mineral structures