TaSe2 — LLMpedia

TaSe2
Name	Tantalum diselenide
Other names	TaSe₂
Formula	TaSe₂
Molar mass	341.82 g·mol⁻¹
Appearance	metallic gray crystals
Density	9.84 g·cm⁻³
Crystal system	hexagonal/trigonal (polymorph-dependent)
Solubility	insoluble in water

Contents

TaSe2 TaSe2 is a layered transition metal dichalcogenide notable for its rich electronic phases, including charge density waves and superconductivity. It has been studied in contexts ranging from condensed matter physics to materials science at institutions such as Max Planck Society, Stanford University, Massachusetts Institute of Technology, Harvard University. Research on TaSe2 connects to experiments performed at facilities including CERN, Brookhaven National Laboratory, Argonne National Laboratory.

Introduction

TaSe2 is a compound comprising Tantalum and Selenium that crystallizes in multiple polymorphs with layered structures. Interest in TaSe2 intensified after observations linking its low-temperature behavior to phenomena explored at Bell Labs and in theoretical work by researchers affiliated with Princeton University and University of Cambridge. Studies often reference materials such as MoS2, WS2, NbSe2, TiSe2 for comparative analyses in the fields of Condensed Matter Physics, Materials Science, and experimental investigations at facilities like SLAC National Accelerator Laboratory and Lawrence Berkeley National Laboratory.

TaSe2 exhibits polymorphism, with prominent polytypes designated 1T, 2H, and 3R echoing classifications used for other dichalcogenides studied at Imperial College London and University of Oxford. The 1T polytype adopts a trigonal structure analogous to phases characterized in papers from Columbia University and ETH Zurich, while the 2H polytype is hexagonal and often compared with structures investigated at Tokyo Institute of Technology and Seoul National University. Layer stacking and coordination influence interlayer registry, a topic appearing in collaborations involving Kavli Institute for Theoretical Physics and Swiss Federal Institute of Technology Lausanne. Structural transitions are often discussed alongside work on Graphene and heterostructures produced at University of Manchester.

TaSe2 shows complex electronic behavior including incommensurate and commensurate charge density waves (CDWs) that have been the subject of studies at Columbia University, NIST, and Rutherford Appleton Laboratory. The interplay of Fermi surface nesting and electron–phonon coupling in TaSe2 has been analyzed in theoretical frameworks developed at Max Planck Institute for Solid State Research, Los Alamos National Laboratory, and University of Tokyo. Low-temperature superconducting phases are reported in contexts similar to investigations by groups at University of Illinois Urbana-Champaign, University of California, Berkeley, and Yale University. Angle-resolved photoemission spectroscopy (ARPES) experiments at Synchrotron Radiation Source facilities including Diamond Light Source and Advanced Photon Source have mapped band dispersions and CDW gaps, frequently referenced alongside studies of High-temperature superconductivity and Quantum materials.

Synthesis methods for TaSe2 share techniques common to transition metal dichalcogenides investigated at Brookhaven National Laboratory and Oak Ridge National Laboratory, including chemical vapor transport procedures pioneered in reports from University of Cambridge and ETH Zurich. Single crystals are often grown using iodine or bromine transport agents in furnaces like those at Argonne National Laboratory and Paul Scherrer Institute. Mechanical exfoliation and liquid-phase exfoliation approaches, used widely in labs such as University of Manchester and Columbia University, yield few-layer flakes applicable to device fabrication. Thin-film deposition techniques, including molecular beam epitaxy implementations at IBM Research and pulsed laser deposition used at National Institute for Materials Science, enable epitaxial growth on substrates like Sapphire and Silicon carbide.

TaSe2 has metallic conductivity and anisotropic transport resembling properties measured at University of California, Los Angeles and University of Pennsylvania. Its phonon spectra have been characterized in neutron and Raman scattering experiments carried out at ISIS Neutron and Muon Source and Institut Laue-Langevin, respectively. Chemical stability and intercalation chemistry with alkali metals and organic molecules have been explored in studies affiliated with University of Geneva and University of Texas at Austin, paralleling work on battery and intercalation compounds investigated at Argonne National Laboratory and Lawrence Livermore National Laboratory. Optical properties and plasmon responses have been compared with those of Gold and Silver nanoparticles in collaborative research with groups at University of Chicago.

Potential applications for TaSe2 span ultrathin electronics and sensors developed in labs such as Stanford University and MIT Media Lab. Heterostructures combining TaSe2 with Graphene, Hexagonal boron nitride, and Transition metal dichalcogenides have been fabricated at facilities including CNRS and CEA Grenoble for tunneling devices and CDW-based oscillators. Research into memory elements and neuromorphic components cites prototypes produced at Seoul National University, Tsinghua University, and National University of Singapore. Superconducting devices leveraging TaSe2 phases have connections to work at Princeton Plasma Physics Laboratory and quantum information efforts at Google and IBM Quantum.

Key characterization techniques used for TaSe2 include ARPES at Advanced Light Source, scanning tunneling microscopy carried out at IBM Research Zurich, transmission electron microscopy at Max Planck Institute for Microstructure Physics, and Raman spectroscopy performed at Raman Research Institute. Transport measurements in dilution refrigerators are common at Weizmann Institute of Science and Duke University. X-ray diffraction experiments at synchrotron beamlines such as those at European Synchrotron Radiation Facility and National Synchrotron Light Source II resolve superlattice reflections linked to CDW transitions. First-principles calculations employing density functional theory have been produced by groups at Flatiron Institute and Sandia National Laboratories to interpret experimental results.

Category:Transition metal dichalcogenides