Related Experiment Video
Updated: Jul 12, 2026
08:55
Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Emergent Atomic Ordering in Vacancy-Filling Heusler Alloys.
Qizhu Li1, Zirui Dong2, Zongyao Li1
1State Key Laboratory of Optoelectronic Information Acquisition and Protection Technology, Leibniz International Joint Research Center of Materials Sciences of Anhui Province, Institutes of Physical Science and Information Technology, Anhui University, Hefei 230601, China.
Journal of the American Chemical Society
|July 9, 2026
Summary
Vacancy-filling Heusler alloys show ordered atomic arrangements, impacting their properties. TiRu1.5Sb exhibits less ordering and lower thermal conductivity, beneficial for thermoelectric applications.
Area of Science:
- Materials Science
- Solid State Physics
- Crystallography
Background:
- Vacancy-filling Heusler alloys bridge conventional Heusler types.
- Partial vacancy filling and multiatomic components cause occupational disorder.
- This disorder challenges the formation of highly crystalline Heusler compounds.
Purpose of the Study:
- To experimentally observe atomic occupation ordering in Slater-Pauling semiconductors MRu1.5Sb (M = Ti, Zr, Hf).
- To investigate the relationship between structural ordering and thermal transport in these materials.
Main Methods:
- Experimental observation of atomic occupation.
- Analysis of crystallographic site occupancy (Ru on 4c and 4d Wyckoff positions).
- Characterization of supercell structure formation.
Main Results:
- Observed selective Ru occupation on 4c and 4d sites, forming an ordered superstructure.
- TiRu1.5Sb showed less pronounced occupational ordering than ZrRu1.5Sb and HfRu1.5Sb.
- TiRu1.5Sb exhibited anomalously low lattice thermal conductivity due to reduced ordering.
Conclusions:
- Atomic ordering in MRu1.5Sb semiconductors influences their thermoelectric properties.
- The interplay between structural order and thermal transport provides flexibility for vacancy-filling Heuslers in thermoelectrics.
Related Concept Videos
02:37Metallic Solids
Metallic solids such as crystals of copper, aluminum, and iron are formed by metal atoms. The structure of metallic crystals is often described as a uniform distribution of atomic nuclei within a “sea” of delocalized electrons. The atoms within such a metallic solid are held together by a unique force known as metallic bonding that gives rise to many useful and varied bulk properties.
All metallic solids exhibit high thermal and electrical conductivity, metallic luster, and malleability. Many...
All metallic solids exhibit high thermal and electrical conductivity, metallic luster, and malleability. Many...
02:46Electron Configurations
Electron configurations and orbital diagrams can be determined by applying the Aufbau principle (each added electron occupies the subshell of lowest energy available), Pauli exclusion principle (no two electrons can have the same set of four quantum numbers), and Hund’s rule of maximum multiplicity (whenever possible, electrons retain unpaired spins in degenerate orbitals).
The relative energies of the subshells determine the order in which atomic orbitals are filled (1s, 2s, 2p, 3s, 3p, 4s,...
The relative energies of the subshells determine the order in which atomic orbitals are filled (1s, 2s, 2p, 3s, 3p, 4s,...
02:42Valence Bond Theory
Coordination compounds and complexes exhibit different colors, geometries, and magnetic behavior, depending on the metal atom/ion and ligands from which they are composed. In an attempt to explain the bonding and structure of coordination complexes, Linus Pauling proposed the valence bond theory, or VBT, using the concepts of hybridization and the overlapping of the atomic orbitals. According to VBT, the central metal atom or ion (Lewis acid) hybridizes to provide empty orbitals of suitable...
02:45Valence Bond Theory
Overview of Valence Bond Theory
03:02The Aufbau Principle and Hund's Rule
To determine the electron configuration for any particular atom, we can build the structures in the order of atomic numbers. Beginning with hydrogen, and continuing across the periods of the periodic table, we add one proton at a time to the nucleus and one electron to the proper subshell until we have described the electron configurations of all the elements. This procedure is called the aufbau principle, from the German word aufbau (“to build up”). Each added electron occupies the subshell of...
01:29Imperfections in Crystal Structure: Non-Stoichiometric Defects
Non-stoichiometric defects refer to a type of defect in the crystal structure of a compound where the ratio of its constituent elements deviates from the ideal stoichiometric ratio. There are two main types of non-stoichiometric defects: metal excess defects and metal deficiency defects.Metal excess defects occur when there is a slight surplus of metal ions than what is required by the stoichiometric ratio of the compound. For example, heating a sodium chloride crystal in sodium vapor results...