Abstract
The two major classes of unconventional superconductors, cuprates and Fe-based superconductors, have magnetic parent compounds, are layered, and generally feature square-lattice symmetry. We report the discovery of pressure-induced superconductivity in a nonmagnetic and wide band gap 1.95 eV semiconductor, Cu2I2Se6, with a unique anisotropic structure composed of two types of distinct molecules: Se6 rings and Cu2I2 dimers, which are linked in a three-dimensional framework. Cu2I2Se6 exhibits a concurrent pressure-induced metallization and superconductivity at â¼21.0 GPa with critical temperature (Tc) of â¼2.8 K. The Tc monotonically increases within the range of our study reaching â¼9.0 K around 41.0 GPa. These observations coincide with unprecedented chair-to-planar conformational changes of Se6 rings, an abrupt decrease along the c-axis, and negative compression within the ab plane during the phase transition. DFT calculations demonstrate that the flattened Se6 rings within the CuSe layer create a high density of states at the Fermi level. The unique structural features of Cu2I2Se6 imply that superconductivity may emerge in anisotropic Cu-containing materials without square-lattice geometry and magnetic order in the parent compound.
| Original language | English |
|---|---|
| Pages (from-to) | 15174-15182 |
| Number of pages | 9 |
| Journal | Journal of the American Chemical Society |
| Volume | 141 |
| Issue number | 38 |
| DOIs | |
| Publication status | Published - Sep 25 2019 |
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ASJC Scopus subject areas
- Catalysis
- Chemistry(all)
- Biochemistry
- Colloid and Surface Chemistry
Cite this
Pressure-Induced Superconductivity and Flattened Se6 Rings in the Wide Band Gap Semiconductor Cu2I2Se6 . / Cai, Weizhao; Lin, Wenwen; Li, Long Hua; Malliakas, Christos D.; Zhang, Rong; Groesbeck, Matthew; Bao, Jin Ke; Zhang, Dongzhou; Sterer, Eran; Kanatzidis, Mercouri G.; Deemyad, Shanti.
In: Journal of the American Chemical Society, Vol. 141, No. 38, 25.09.2019, p. 15174-15182.Research output: Contribution to journal › Article
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TY - JOUR
T1 - Pressure-Induced Superconductivity and Flattened Se6 Rings in the Wide Band Gap Semiconductor Cu2I2Se6
AU - Cai, Weizhao
AU - Lin, Wenwen
AU - Li, Long Hua
AU - Malliakas, Christos D.
AU - Zhang, Rong
AU - Groesbeck, Matthew
AU - Bao, Jin Ke
AU - Zhang, Dongzhou
AU - Sterer, Eran
AU - Kanatzidis, Mercouri G.
AU - Deemyad, Shanti
PY - 2019/9/25
Y1 - 2019/9/25
N2 - The two major classes of unconventional superconductors, cuprates and Fe-based superconductors, have magnetic parent compounds, are layered, and generally feature square-lattice symmetry. We report the discovery of pressure-induced superconductivity in a nonmagnetic and wide band gap 1.95 eV semiconductor, Cu2I2Se6, with a unique anisotropic structure composed of two types of distinct molecules: Se6 rings and Cu2I2 dimers, which are linked in a three-dimensional framework. Cu2I2Se6 exhibits a concurrent pressure-induced metallization and superconductivity at â¼21.0 GPa with critical temperature (Tc) of â¼2.8 K. The Tc monotonically increases within the range of our study reaching â¼9.0 K around 41.0 GPa. These observations coincide with unprecedented chair-to-planar conformational changes of Se6 rings, an abrupt decrease along the c-axis, and negative compression within the ab plane during the phase transition. DFT calculations demonstrate that the flattened Se6 rings within the CuSe layer create a high density of states at the Fermi level. The unique structural features of Cu2I2Se6 imply that superconductivity may emerge in anisotropic Cu-containing materials without square-lattice geometry and magnetic order in the parent compound.
AB - The two major classes of unconventional superconductors, cuprates and Fe-based superconductors, have magnetic parent compounds, are layered, and generally feature square-lattice symmetry. We report the discovery of pressure-induced superconductivity in a nonmagnetic and wide band gap 1.95 eV semiconductor, Cu2I2Se6, with a unique anisotropic structure composed of two types of distinct molecules: Se6 rings and Cu2I2 dimers, which are linked in a three-dimensional framework. Cu2I2Se6 exhibits a concurrent pressure-induced metallization and superconductivity at â¼21.0 GPa with critical temperature (Tc) of â¼2.8 K. The Tc monotonically increases within the range of our study reaching â¼9.0 K around 41.0 GPa. These observations coincide with unprecedented chair-to-planar conformational changes of Se6 rings, an abrupt decrease along the c-axis, and negative compression within the ab plane during the phase transition. DFT calculations demonstrate that the flattened Se6 rings within the CuSe layer create a high density of states at the Fermi level. The unique structural features of Cu2I2Se6 imply that superconductivity may emerge in anisotropic Cu-containing materials without square-lattice geometry and magnetic order in the parent compound.
UR - http://www.scopus.com/inward/record.url?scp=85072628274&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85072628274&partnerID=8YFLogxK
U2 - 10.1021/jacs.9b06794
DO - 10.1021/jacs.9b06794
M3 - Article
C2 - 31480843
AN - SCOPUS:85072628274
VL - 141
SP - 15174
EP - 15182
JO - Journal of the American Chemical Society
JF - Journal of the American Chemical Society
SN - 0002-7863
IS - 38
ER -