The Powderly Group seeks to develop and utilize new synthetic pathways to discover extended solids with magnetic, electronic, and non-trivial topological properties of interest in quantum information science and to explore new fundamental bonding in materials.
Lab members apply synthetic and characterization techniques including solution-phase synthesis of nanoclusters and metal complexes, in situ X‑ray diffraction and thermal analysis to probe solid-state transformations up to 1000 °C, and variable-temperature magnetic, electronic, and thermal characterization to explore materials’ quantum behaviors.
Direction 1: Assembly of magnetic cluster-organic frameworks
Recently, a neutral magic-sized gold cluster, Au25(SR)18 (R = inorganic ligand), has been found to host a spin-1/2 moment that is delocalized over its central icosahedron. As the electronic structure of the core cluster is robust to external geometry changes, these clusters may serve as nodes in new 2D assembled materials. Thus far, the scientific literature lacks detailed study of the assembly of such spin-1/2 clusters into two-dimensional lattices with covalent, conjugated linkers that can facilitate magnetic coupling. The Powderly Group seeks to determine relationships between the sign and strength of magnetic coupling between cluster “superatoms” and molecular linker chemistry, size, and geometry. This study aims to realize guiding rules that can be used to design 2D spin-nets with predictable magnetic properties, towards quantum spin liquids, ferromagnets, and networks of spin quantum bits.
Direction 2: Diffusion-suppressed routes to intermetallics with quantum properties
Intermetallic transition-metal-bismuth (M-Bi) solid-state compounds have demonstrated intriguing magnetic and electronic properties including ferromagnetism in MnBi, non-trivial topological phenomena in Na3Bi, and superconductivity, or the perfect conduction of electrons with zero resistance below a critical temperature, in CoBi3, α-NiBi, and NiBi3. Many other binary metal-bismuth systems do not show any thermodynamically stable compounds in their phase diagrams and even demonstrate immiscibility upon melting. Despite this, many metastable intermetallic compounds in these binaries have been computationally predicted to exist, with energies slightly above the phase-segregated elements, and have the potential to host exotic properties.
A compelling route to realize these metastable materials is to kinetically “trap” the quickest forming phases by limiting thermal energy and diffusion time. By achieving atomic-level mixing of precursors, diffusion is sidestepped completely, offering a powerful pathway to the synthesis of metastable phases. The Powderly Lab will synthesize previously unobserved solid-state M–Bi compounds through moderate-temperature, ambient-pressure thermolysis of heterobimetallic complexes in which the desired M–Bi bond already exists, while simultaneously using in situ thermal analysis and diffraction techniques to study the thermodynamic landscape.
