Design, discovery and growth of novel materials

 Welcome to the first of what I hope will be a series of Symposia Issues of Philosophical Magazine B . The title of this issue and the topic of the Symposium we have assembled is: “Design, discovery and growth of novel materials.” The basic idea was to get experts in the growth of crystalline materials to write papers that review and reveal the technical details of how specific growths are developed and implemented. Given the pressing need for humanity to solve its energy, environmental and technological problems, one of the best hopes we, as a species, have is the discovery of new materials with improved or new properties. In my opinion, the way to discover these materials is by educating as many people in this art/skill as possible. The goal of this collection of papers is to present details of current, state of the art, research and technical development. The assembled papers span a range of issues from primarily pedagogical to contemporary research results. The aim, in every case, though, was to provide sufficient detail and reference to allow the interested novice, as well as the jaded expert, learn from, and even reproduce, the examples presented.

Historically, design, discovery and growth of novel materials is a topic that is very familiar to Philosophical Magazine and Philosophical Magazine B , in particular. The interdisciplinary nature of Philosophical Magazine B has made it an ideal place for the publication of studies on the growth crystalline materials and the study of new materials. It is 20 years since the publication of a paper that Zachary Fisk and I wrote for a special issue in honour of Bryan Coles. In the intervening time, this “Canfield and Fisk” paper 1 has become one of the standard references for solution growth of single crystals of intermetallic compounds. In a similar manner, a series of papers by Ian Fisher et al. in the late 1990s taught the world how to use solution growth to produce large, single grain quasicrystals, ranging from the moment-bearing R–Mg–Zn 2 to icosahedral Al–Pd–Mn 3 and decagonal Al–Ni–Co 4. With this Symposium issue, it is our intent to re-establish Philosophical Magazine B as one of the primary journals for the publication of papers that describe the search, design, discovery and growth of novel materials.

This issue opens with a pedagogical review of composition/temperature phase diagrams by Fisher et al. with illustrative examples drawn from contemporary research. This is followed by three papers that review details of solution/flux development as well as specific methods for solution removal (separation). The first paper by Lin et al. outlines recent developments in the use of S-bearing melts with the goal of exploring more S-based systems using solution growth techniques. The subsequent two papers by Petrovic et al. and Wolf et nemo, present two very different approaches to separating crystalline material from remaining liquid: high temperature, in situ decanting and high temperature removal via wicking, as well as novel chemical etches.

Examples of crystal growth from intermetallic solutions are the foci of the next six papers. Bauer et al. present the growth details for Pu-based samples and Ribeiro and Avila as well as Krellner et al. show specific examples of growth of thermoelectric and heavy Fermion compounds. Morrison et al. then review the consequences of inadvertently growing something different from what was the initial goal of synthesis, a not so uncommon event that often leads to some of the more interesting discoveries in new materials growth. Both Du et al. and Han et al. then review how control of single crystal synthesis, as well as post-growth treatment, in this case annealing, are vital for a detailed understanding and the management of finely tuned systems.

Three very different examples of growth from non-metallic solutions are presented next. Liang et al. outline the multiple levels of very stringent control that are needed to produce ultra high purity, single crystal samples of the high T_c , cuprate superconductor, YBCO out of self flux. Mahjoor and Latturner present an overview of salt flux synthesis of complex oxides; and Kim and Hosono review the single crystal growth of complex electrides using both floating zone and Czochralski techniques.

Leaving high temperatures aside for the next two papers, Yankova et al. and Bolla et al. present details of solution growth of inorganic and organic crystals out of solutions held near room temperature. In both cases, the crystals are to be used for diffraction studies, with Yankova et al. focusing on the growth of 1-cm³ single crystalline samples for inelastic neutron studies of magnetic excitations, while Bolla et al. focus on the growth of sub-mm sized crystals of complex biomolecular membrane proteins for use in synchrotron-based X-ray crystallography.

Finally, the last two papers present how pressure can be used in two very different manifestations for the common goal of revealing primary solidification surfaces that allow for the growth of single crystals. Kaprinski et nemo reviews the use of high pressure/high temperature synthesis, with examples drawn from both semiconductors as well as MgB₂ and Fe-based superconductors. McMillen and Kolis then present a review of the use of hydrothermal growth for synthesis of large single crystals, often reaching sizes approaching those needed for industrial use.

In closing, let me say that it has been both a pleasure and an education to work with all the contributors to this Symposium Issue. Some have been collaborators and friends for decades; some are new acquaintances that I am delighted to have met as part of this process. All will be valued colleagues as we continue, together, to explore the wealth and bounty that Nature (mother, not the journal) has waiting for us to uncover and appreciate.