The 16th International Conference on Quasicrystals (ICQ16) was held in Nancy, France, from June 22nd to 27th, 2025. This is one of a series following the 1st workshop in Les Houches, France; the 2nd in Beijing, China; the 3rd Meeting in Vista-Hermosa, Mexico; the 4th Conference in St Louis, USA; the 5th in Avignon, France; the 6th in Tokyo, Japan; the 7th in Stuttgart, Germany; the 8th in Bangalore, India; the 9th in Ames, USA; the 10th in Zürich, Switzerland; the 11th in Sapporo, Japan; the 12th in Cracow, Poland; the 13th in Kathmandu, Nepal; the 14th in Kranjska Gora, Slovenia; and the 15th in Tel-Aviv, Israel.

ICQ16 covered a wide range of topics on quasicrystals, including:

• Formation, growth and phase stability
• Structure and modeling
• Mathematics of quasiperiodic and aperiodic structures
• Physical properties: transport, magnetic, dynamical, mechanical etc.
• Surfaces and overlayers, reactivity, catalysis
• New Frontiers, strongly correlated electron systems, quantum materials
• Related topics: incommensurate/modulated structures, metallic glass, high entropy alloys, complex metallic alloys, cage compounds, clusters etc.
• Metamaterials: polymer, macro molecules, photonic/phononic crystals, oxide etc.
• Applications

The conference (https://icq16-conference.com/) offered an excellent opportunity for researchers working on quasicrystals and related topics to discuss emerging research, exchange ideas, establish dialogues and encourage active collaborations with other research groups, hence promoting material science and engineering. It brought together the best scientists in the world who made a major contribution to recent developments in this field.

ICQ16 was attended by 85 participants from 18 countries. There were 15 scientific sessions, 15 invited talks, 37 contributed talks, as well as 2 poster sessions. The conference was truly interdisciplinary - comprising theoretical and experimental physicists, mathematicians, chemists and materials scientists.

The 2025 Jean-Marie Dubois Award for Excellence in Quasicrystal Research was attributed to Ryuji Tamura, Professor at Tokyo University of Science, Japan. The Jean-Marie Dubois Award was established to recognize important sustained research on any aspect of quasicrystals in the last 10-year period preceding the award. Professor Ryuji Tamura received this award in recognition of his outstanding achievements in establishing the long-range magnetic orderings in periodic approximants and quasicrystals, with the recent discovery of ferromagnetic and antiferromagnetic orders in Tsai-type icosahedral quasicrystals.

In addition, the support from the International Union of Crystallography (IUCr) permitted 7 travel grants to be attributed to young scientists. We also gratefully acknowledge the financial supports from the European Integrated Center for the Development of New Metallic Alloys and Compounds (ECMetAC), the Université de Lorraine, the Métropole du Grand Nancy, Edwards Company and Vinci Technologies.

The next International Conference on Quasicrystals (ICQ17) will be held in Sendai, Japan, in 2028.

Vincent Fournée, Conference Chair.
Julian Ledieu, Conference Co-chair.

Santiago García-Granda IUCr President 2023–

In approximately one year, we will have our triennial meeting in Calgary, Canada, including our 27th Congress and General Assembly. This is the most important event in the IUCr calendar, and we have been preparing for it for two years since the end of our 26th Congress in Melbourne, Australia.

We are on our way to our centennial as an organization and already have memories of important previous events on five continents. The history of the IUCr is particularly significant in North America as we have met on six occasions: Montreal (1957), Stony Brook (1969), Ottawa (1981), Seattle (1996), Montreal (2014) and, in particular, the first Congress and General Assembly took place at Harvard in 1948. This letter gives me the opportunity to express my strongest support for academic institutions like Harvard University, where this Union was first presented, in its fight for the principles that underpin academic institutions: freedom, respect, fraternity, rigor and independence. These are spaces for free thought in the face of impositions, and which constitute the foundation of progress and the future of humanity.

The world and science have changed a lot since 1948, and not always in the right direction. In these times, we may be threatened by changes in society or by conflict, but the IUCr continues to base its actions on scientific truth and to support the free movement of scientists and collaboration without borders. This summer as a show of support for the crystallographers and structural scientists of Ukraine, the Executive Committee and Finance Committee of the IUCr will hold their meetings at ECM35, which has been relocated to Poznań.

Other regional association meetings will take place in Algiers, Algeria (AfCA), Fortaleza, Brasil (LACA) and Taipei, Taiwan (AsCA) in October and December of this year. I will personally attend the AfCA and AsCA meetings. Last year, I attended the ECM34/EPDIC18 in Padova, the LACA meeting in Montevideo and, with the Finance Committee (FC) and Executive Committee (EC), the ACA in Denver. The American Crystallographic Association recently held its 75th Annual Meeting in Lombard, Illinois.

The IUCr would like to support as many structural scientists as possible in their endeavours through travel support and other initiatives. In order to do this we must support our journals. Any excess funds from our publishing activities go, via our Meeting Support Committee, to young researchers to help them attend conferences and schools. The commitment of our community of structural scientists to publish in our 10 IUCr Journals is vital to fund such initiatives. This call is especially important for the younger generations of structural scientists and their senior supervisors to submit their research to our journals. Also, the involvement of industrial research within our Union can help formalize our connection with this productive sector and ensure that our journals are also a means of agile communication of the structural science research carried out there. Our journals guarantee rigorous and expert scientific review of the manuscripts they publish. They feature in the highest rankings for structural science and have the option of affordable open access.

Looking forward to next year, the call for nominations for the IUCr Ewald, W. H. & W. L. Bragg, and Struchkov awards, which will be presented in Calgary, is now open. It is important that all eligible candidates submit their nominations to ensure the quality and diversity of the selection process by the selection committees. The deadline for all nominations is 30 November.

While our more than 75 years of history and the achievements of our pioneers and the brilliant generations that followed, whom we admire and respect, are very important, it is essential to look to the future. That is why, both at regional association level and through the newly formed IUCr Early Career Scientists Division (ECSD), young researchers must speak out and gradually take the lead in our Union as the only guarantee for the future. For our publications, the Early Career Researcher Boards are taking shape and will have an influence on what is published in our journals. Refreshing the Commission members and consultants and the Executive Committee officers at the Congress next year is also an excellent opportunity to include younger researchers and increase diversity.

The IPC's hard work is nearing completion to ensure the best programme for an excellent Congress in Calgary. The work of Louise Dawe, Amy Sarjeant and Stephen Burley has been intense and excellent, as has that of all the representatives of the IUCr Commissions and Committees. The contribution of, and experience from, the Melbourne Congress and the effective link with our future Congress in Berlin in 2029 has been very important. Brendan Kennedy and Manfred Weiss, together with the Co-chairs of IUCr2026, will enable us to correct errors and improve the guidelines for future Congresses. We may not have been able to have all the speakers we would like but we have aimed for maximum diversity without compromising the appeal and high scientific level of our event. I would like to draw your attention to four microsymposia proposed by the new IUCr ECSD and the EC itself, 'Career panel’, ‘Current challenges and new strategies for the IUCr Journals’, ‘Inclusion and belonging in structural science’ and `IUCr purpose vision and values’. It is important that we all participate in the meeting, express our opinions and provide contributions to define the future of the IUCr, and make it attractive to new generations of structural scientists, expanding our community in new directions.

As usual, I end this letter with deep gratitude to all those who form and make our organization work, the Regional Associates, the IUCr Commissions and Committees, Editors, Co-editors, referees and authors of our journals, our Chester staff and all individual structural scientists.

Thanks to IUCr Newsletter Editor Mike Glazer, and his team, and thanks to all contributors for making possible, as with every issue, a new issue that continues to be the reference communication for our community.

Thank you all for helping to keep the momentum of the IUCr going, wherever you are in the world.

2023 Gjønnes Medal winner Jian-Min Zuo

In Volume 33, Issue 2, we omitted the 2020 recipients of the IUCr Gjønnes Medal in Electron Crystallography.

The medal was awarded to Sven Hovmöller (Professor Emeritus, Stockholm University, Sweden) and Ute Kolb (Head, Centre for High Resolution Electron Microscopy, Johannes Gutenberg-Universität, Mainz, Germany) for their pioneering work in the field of electron crystallography, particularly for developing 3D electron diffraction techniques.

The corrected article is available here: https://www.iucr.org/news/newsletter/volume-33/number-2/cfn-2026-gjnnes-medal.

The phase-seeding method proposed by Carrozzini et al. [(2025), Acta Cryst. A81, 188–201] introduces a strategy for integrating artificial intelligence (AI) with established ab initio phasing techniques. Rather than presenting an AI-based phasing solution itself, the authors demonstrate how traditional crystallographic methods can be significantly enhanced if provided with a small subset of approximate phase values – a `phase seed' – that could, in principle, be generated by a machine learning model. By discretizing phase values into a few angular bins, the method transforms the continuous phase problem into a classification task, thereby reducing the computational burden on AI training. This hybrid approach shows promise for improving structure solution, particularly for large and complex non-centrosymmetric crystals, and opens a pathway for future AI-assisted crystallographic workflows.

 

This article was originally published in Acta Cryst. (2025). A81, 251-253.

MAX IV in association with LINXS is pleased to announce a symposium on “Scientific achievements through serial crystallography”, marking the start of user operations at the MicroMAX Beamline. The program will take place 22nd-24th September at Lund and will feature talks, discussions, and networking with experts in the field — offering insights into emerging directions in structural biology. For registration and further information, visit the MicroMAX symposium webpage. Registration deadline is the 1st of September.

Serial crystallography opens possibilities to study protein dynamics on a wide range of time scales and irreversible reactions. It is also a powerful method to study protein structures at room temperature as the impact of radiation damage is reduced. Serial crystallography at X-ray free-electron lasers and synchrotrons has applications that extend beyond structural biology.

This symposium will showcase some of the exciting scientific advances achieved through serial crystallography and time-resolved crystallography, in structural biology and other areas.

It will feature presentations from invited speakers, and selected oral presentations based on submitted abstracts and poster sessions. The symposium will be held at LINXS (http://www.linxs.se) at its new location in the Science Village located between the MAX IV Laboratory (https://www.maxiv.lu.se) and the European Spallation Source (http://www.ess.eu).

Attendees will also be invited for a tour of the MAX IV beamlines on the evening of 23rd September.

Registrations are now open for the TR+ workshop: "Time-resolved methods for the Life Sciences at MAX IV" taking place in Lund on 24th-26th September. The TR+ workshop will provide exciting insight into the broad range of synchrotron-based techniques available at MAX IV to investigate dynamics on a variety of length scales and timescales in biomolecules using X-ray spectroscopy, scattering, serial crystallography, and combined methods.

This workshop will focus on the practical considerations in performing time-resolved synchrotron studies including sample preparation and delivery, reaction triggering methods, and large data analysis and interpretation. Early career and established researchers interested in pursuing new techniques are encouraged to attend.

Scientific applications and expert panel discussions will showcase the information provided by the various methods. Attendees are also encouraged to contribute to a poster session and invited to visit MAX IV for tours and one-on-one meeting opportunities with beamline scientists to discuss their next experiment.

Learn more & register

Figure 1. Experimental geometry and fundamental principles of XCCA (after Möller et al., 2025). A single-shot diffraction pattern captures a 2D slice of the 3D intensity distribution in reciprocal space, determined by the geometry of the Ewald sphere. In XCCA, azimuthal intensity correlations of the 2D pattern are analyzed to access the 3D reciprocal space.

Crystallization is a non-equilibrium process involving the formation and evolution of order from disorder. While much progress has been made in understanding stable crystal structures, the transient intermediate states that arise during the early stages of crystallization – often containing structural defects – remain elusive (Lupi et al., 2017; Niozu et al., 2021; De Yoreo, 2022). These defect-containing structures may play a pivotal role in determining both the nucleation rate (Lupi et al., 2017; Möller et al., 2024) and the final crystal morphology, yet our current understanding of them remains limited due to their fleeting nature.

There are several technical challenges associated with in situ investigations of crystallization processes. Crystalline defects can be probed by electron microscopy; however, such measurements are typically ex situ and cannot be easily extended to statistical investigations of large ensembles. Powder X-ray diffraction can be used for in situ investigations of the crystallization process on large ensembles, but it usually provides a one-dimensional (1D) intensity profile that corresponds to the orientational average of the three-dimensional (3D) intensity in reciprocal space. Crystalline defects can cause peak broadening in the 1D line profile; however, it is often challenging to distinguish between different types of defects solely based on the 1D information.

In the current issue of IUCrJ, Möller and co-workers report on the structures of disordered crystals forming in a supercooled noble-gas liquid (Möller et al., 2025). Using an advanced scattering technique that combines femtosecond X-ray diffraction and X-ray cross-correlation analysis (XCCA) (Wochner et al., 2009; Altarelli et al., 2010; Kirian, 2012), they accessed the 3D reciprocal space of the disordered crystals and uncovered the structural evolution. They identified a decrease in stacking-fault occurrences in face-centered-cubic structures along the liquid jet – an insight that would be difficult to extract from the 1D powder pattern.

To understand how the XCCA technique provides such detailed structural insights, we briefly outline its fundamental principles, as illustrated in Fig. 1. When a femtosecond X-ray pulse illuminates a crystal, the resulting diffraction pattern captures only a two-dimensional (2D) slice of the 3D intensity distribution in reciprocal space, constrained by the geometry of the Ewald sphere. Reconstructing the full 3D information from such 2D slices is non-trivial without prior knowledge of crystal orientations. A common initial analysis is to derive the radial intensity profile of a diffraction image accumulated over many X-ray shots, yielding the familiar 1D powder diffraction pattern. To go beyond this 1D representation, one can analyze the correlations in the azimuthal intensity distribution of single-shot images. These angular correlations encode intrinsic features of the 3D intensity distribution in reciprocal space. Thus, XCCA provides a pathway toward reconstructing the 3D information, even without orientational alignment of the crystals.

From an experimental perspective, successful application of XCCA requires X-ray pulses shorter than the rotational diffusion timescale of the crystals, so that the structure is not moving significantly during an X-ray exposure (Mendez et al., 2016). In addition, sufficient statistical sampling, i.e., a large number of single-shot diffraction patterns, is essential for reliable correlation analysis and extraction of meaningful structural information (Möller et al., 2025). To satisfy these requirements, Möller et al. employed the unique beam properties of the European X-ray free-electron laser (XFEL), including femtosecond pulse duration and a large number of pulses per second.

While some previous studies have applied femtosecond XCCA to investigate atomic-scale defects (Mendez et al., 2014; Mendez et al., 2016; Niozu et al., 2020), these earlier works primarily focused on correlations between a limited number of scattering vectors, which restricted their ability to explore the full 3D reciprocal space. Möller and co-workers advanced this approach by analyzing the entire 3D correlation map, thereby enabling a more comprehensive assessment of the 3D reciprocal space. They further performed numerical simulations of the correlation map and demonstrated that structural properties such as stacking fault density and crystal size can be disentangled by focusing on different features in the correlation map. Based on specific peak-broadening features in the correlation map, they identified a time-dependent reduction in stacking fault density, suggesting annealing or growth of the crystals as they travel along the liquid jet.

Future applications of femtosecond XCCA will enable even more detailed analyses of disordered structures forming in crystallization processes. As Möller et al. mentioned, the next steps will involve probing the earliest stages of crystal nucleation and growth, as well as developing a model-free approach to reconstruct the 3D reciprocal space from the correlation maps. Such advancements will ultimately enable a more comprehensive understanding of crystallization processes in a diverse range of materials, from ice formation in the atmosphere (Lupi et al., 2017) to the controlled synthesis of advanced materials.

References

Altarelli, M., Kurta, R. P. & Vartanyants, I. A. (2010). Phys. Rev. B 82, 104207.

De Yoreo, J. J. (2022). Proc. Natl Acad. Sci. USA 119, e2121661119.

Kirian, R. A. (2012). J. Phys. B At. Mol. Opt. Phys. 45, 223001.

Lupi, L., Hudait, A., Peters, B., Grünwald, M., Gotchy Mullen, R., Nguyen, A. H. & Molinero, V. (2017). Nature 551, 218–222.

Mendez, D., Lane, T. J., Sung, J., Sellberg, J., Levard, C., Watkins, H., Cohen, A. E., Soltis, M., Sutton, S., Spudich, J., Pande, V., Ratner, D. & Doniach, S. (2014). Phil. Trans. R. Soc. B 369, 20130315.

Mendez, D., Watkins, H., Qiao, S., Raines, K. S., Lane, T. J., Schenk, G., Nelson, G., Subramanian, G., Tono, K., Joti, Y., Yabashi, M., Ratner, D. & Doniach, S. (2016). IUCrJ 3, 420–429.

Möller, J., Caresana, M., Schottelius, A., Lehmkühler, F., Boesenberg, U., Caupin, F., Dallari, F., Ezquerra, T. A., Fernández, J. M., Gelisio, L., Goy, C., Hallmann, J., Kalinin, A., Kim, C., Kurta, R. P., Lapkin, D., Mambretti, F., Scholz, M., Shayduk, R., Steinbrügge, R., Trinter, F., Vartanyants, I. A., Zozulya, A., Galli, D. E., Grübel, G., Madsen, A. & Grisenti, R. E. (2025). IUCrJ 12, 462–471.

Möller, J., Schottelius, A., Caresana, M., Boesenberg, U., Kim, C., Dallari, F., Ezquerra, T. A., Fernández, J. M., Gelisio, L., Glaesener, A., Goy, C., Hallmann, J., Kalinin, A., Kurta, R. P., Lapkin, D., Lehmkühler, F., Mambretti, F., Scholz, M., Shayduk, R., Trinter, F., Vartaniants, I. A., Zozulya, A., Galli, D. E., Grübel, G., Madsen, A., Caupin, F. & Grisenti, R. E. (2024). Phys. Rev. Lett. 132, 206102.

Niozu, A., Kumagai, Y., Hiraki, T. N., Fukuzawa, H., Motomura, K., Bucher, M., Asa, K., Sato, Y., Ito, Y., You, D., Ono, T., Li, Y., Kukk, E., Miron, C., Neagu, L., Callegari, C., Di Fraia, M., Rossi, G., Galli, D. E., Pincelli, T., Colombo, A., Owada, S., Tono, K., Kameshima, T., Joti, Y., Katayama, T., Togashi, T., Yabashi, M., Matsuda, K., Bostedt, C., Ueda, K. & Nagaya, K. (2021). Proc. Natl Acad. Sci. USA 118, e2111747118.

Niozu, A., Kumagai, Y., Nishiyama, T., Fukuzawa, H., Motomura, K., Bucher, M., Asa, K., Sato, Y., Ito, Y., Takanashi, T., You, D., Ono, T., Li, Y., Kukk, E., Miron, C., Neagu, L., Callegari, C., Di Fraia, M., Rossi, G., Galli, D. E., Pincelli, T., Colombo, A., Owada, S., Tono, K., Kameshima, T., Joti, Y., Katayama, T., Togashi, T., Yabashi, M., Matsuda, K., Nagaya, K., Bostedt, C. & Ueda, K. (2020). IUCrJ 7, 276–286.

Wochner, P., Gutt, C., Autenrieth, T., Demmer, T., Bugaev, V., Ortiz, A. D., Duri, A., Zontone, F., Grübel, G. & Dosch, H. (2009). Proc. Natl Acad. Sci. USA 106, 11511–11514.

 

This article was originally published in IUCrJ (2025). 12, 419-420.

Figure 1. An ORTEP representation of an arbitrary atom with different ratios of lowest and highest principal-axis displacement parameters, i.e. reflecting the amount of asphericity, with most isotropic on the left (in blue) and most anisotropic on the right (in red). Adapted from Deringer et al., 2014, with permission from The Royal Society of Chemistry.

This article is part of a focused issue on Quantum Crystallography.

Although the method of crystal structure determination by diffraction is well over a century old (Friedrich et al., 1913), its importance continues to grow, and at an increasing rate. We have become accustomed to the fact that every crystalline material is examined sooner or later using diffraction, and ultimately all atomic positions are determined in three-dimensional space, meaning that chemical analysis is also provided free of charge via a detour. Once the atomic positions have been found, quantum-chemical calculations can be carried out, because the sheer existence of the substance, the molecule, the material ultimately needs to be understood. What a wonderful method – quite astonishing. And what would science look like if this method didn't exist?

Nonetheless, even in a rock-solid crystal the atoms are not standing still, not even at absolute zero temperature (if only for quantum-mechanical reasons, thus spoke Heisenberg). And at finite temperatures the atoms have to move even more, and they have to do so collectively, otherwise it wouldn't remain a crystal. So collective vibrations in the crystal – called phonons – become excited, and it is precisely these movements that change the X-ray or neutron intensities. Incidentally, contrary to original fears, the moving atoms also result in sharp diffraction images, despite their movement. This is the subject of the topical review by Hoser and Madsen (2025), two proven experts in this field, in the current issue of IUCrJ, using the properly chosen example of small (everyday) molecules.

Their work provides a competent overview of the significance and modeling of thermal movements in crystals. The protagonist is the so-called Debye–Waller factor (Debye, 1913; Waller, 1923), which is mathematically attached to the atomic form factor as a correction term. Considering the pure atom–beam interaction, it is precisely the Debye–Waller factor that causes the observed diffraction intensities to decrease at finite temperature due to the atom oscillating back and forth. If the intensities can be measured precisely enough, the thermal movement can also be reconstructed precisely upon modeling these intensities, regardless of which radiation source is used.

Originally it looked – partly due to poor data, partly due to a lack of theory – as if atomic motion were isotropic (i.e. the same in all spatial directions). For high-symmetry crystals (cubic table salt is a good example) this crude assumption is sufficient, but not so in more complex cases. In molecular crystals, for instance, the atoms are bound to certain neighboring atoms (but not to others), so the thermal movement can and will be highly anisotropic, because it reflects the differing chemical bondings. Hence, in 2025, we routinely talk about anisotropic displacement parameters (ADPs), which are needed to describe atomic motion mathematically. To do so, a symmetrical 3 × 3 matrix – typically denoted as U – is required. Its elements would be very difficult to visualise if C. K. Johnson had not demonstrated, exactly 60 years ago using the `Oak Ridge Thermal Ellipsoid Plot' (ORTEP) program, how to represent the thermal movement graphically (Johnson, 1965). Fig. 1 shows a typical case in an idealized form. In a figurative sense, we `see' how the atom moves or displaces or oscillates, because the blue atom on the left looks isotropic but as we move towards the right-hand side of the figure the vertical oscillation component (one main axis) becomes increasingly larger, as the quotient for the orange and red atoms indicates. The ellipsoid could of course also be tilted in space, for which the non-diagonal elements of U would then be needed.

So much for the gray theory, but life is much more colorful. In the practice of crystal structure analysis, the anisotropic displacement parameters are routinely used to refine a crystal structure as perfectly as possible, under the plausible assumption – but what an assumption! – that these ADPs actually describe the atomic motions correctly. However, it is also conceivable that the ADPs conceal or disguise certain residual errors or even incorrect models, as `botch' parameters, so to speak. So do the ADPs actually reflect the thermal motion? Or is the structural model incorrect, possibly disordered? How can one demonstrate that? Could powerful theory help, especially in experimentally difficult situations?

Using small molecules as the most fitting examples, Hoser and Madsen discuss various approaches to modeling the atomic thermal motion in a very pedagogical way, starting with lattice dynamics and dispersion analysis of various phonon modes in reciprocal space. They continue with the more-or-less direct calculation of the Debye–Waller factor using (empirical) force fields, ab initio calculations and molecular dynamics simulations. A real challenge lies in the anharmonic movements that lead to, for example, thermal expansion of the crystal, and which can be described using extended formulas (say, Gram–Charlier series). High-resolution diffraction data as complete as possible are essential here, in addition to a correct structural (and ideally also electronic structure) model. The challenges of hydrogen atoms and the comparability of X-ray and neutron diffraction are also explained, including approaches for validating ADPs.

In their review, Hoser and Madsen finally discuss specialized models (e.g. `rigid body' and `TLS' = translation/libration/screw analysis) that allow the interpretation of collective motions of groups of atoms belonging together, and they explain the SHADE approach for the treatment of hydrogen atoms bonded to C, N and O. In addition, thermodynamic quantities such as vibrational entropies or heat capacities can be estimated from really precise ADPs. All this results in a close interplay between precise experiments, advanced theory and computer simulations, these days known as `quantum crystallography', to capture precisely thermal motion (and possible deviations from that) in small-molecule crystals. In the future, diffuse scattering will also be looked at more closely, and machine learning will be given its chance.

That being said, a lot has happened since 1913, and in view of more precise measurements and – the subject of their topical review – considerably more powerful modeling methods, nothing stands in the way of the quantitative analysis of atomic movements. There is a great deal of additional information in these movements that is worth exploiting, as nicely demonstrated by Hoser and Madsen.

References

Debye, P. (1913). Annalen Phys. 348, 49–92.

Deringer, V. L., Stoffel, R. P., Togo, A., Eck, B., Meven, M. & Dronskowski, R. (2014). CrystEngComm 16, 10907–10915.

Friedrich, W., Knipping, P. & Laue, M. (1913). Annalen Phys. 346, 971–988.

Hoser, A. & Madsen, A. Ø. (2025). IUCrJ 12, 421–434.

Johnson, C. K. (1965). ORTEP: A Fortran Thermal-Ellipsoid Plot Program for Crystal Structure Illustrations. Report ORNL-3794 (Rev.), Union Carbide Corp. and Oak Ridge National Laboratory, Tennessee, USA.

Waller, I. (1923). Z. Phys. 17, 398–408. 

 

This article was originally published in IUCrJ (2025). 12, 417-418.

Richard Dronskowski is the Chair of Solid-State and Quantum Chemistry.