TY - JOUR
T1 - Stability of numerous novel potassium chlorides at high pressure
AU - Zhang, Weiwei
AU - Oganov, Artem R.
AU - Zhu, Qiang
AU - Lobanov, Sergey S.
AU - Stavrou, Elissaios
AU - Goncharov, Alexander F.
N1 - Funding Information:
This work is funded by NSFC (Nos 11474355, 21403297, 61474142), Chinese Universities Scientific Fund (No. 2015LX002), DaBeiNong Young Scholars Research Plan, the Government of Russian Federation (No. 14.A12.31.0003) and Foreign Talents Introduction and Academic Exchange Program (No. B08040). A.F.G. acknowledges support from the Army Research Office and NSF-EAR. X-ray diffraction experiments were performed at GeoSoilEnviroCARS (Sector 13), Advanced Photon Source (APS), Argonne National Laboratory and Petra III, DESY, Hamburg, Germany. GeoSoilEnviroCARS is supported by the National Science Foundation-Earth Sciences (EAR-1128799) and Department of Energy-Geosciences (DE-FG02-94ER14466). The research leading to these results has received funding from NSFC (No. 21473211) and the European Community's Seventh Framework Programme (FP7/2007-2013) under grant agreement No. 312284. Use of the Advanced Photon Source was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357. PETRA III at DESY is a member of the Helmholtz Association (HGF). S.S.L. was partly supported by the Ministry of Education and Science of Russian Federation (No. 14.B25.31.0032). Work of E.S. was performed under the auspices of the U. S. Department of Energy by Lawrence Livermore National Security, LLC under Contract DE-AC52-07NA27344.
PY - 2016/5/23
Y1 - 2016/5/23
N2 - K-Cl is a simple system displaying all four main types of bonding, as it contains (i) metallic potassium, (ii) elemental chlorine made of covalently bonded Cl 2 molecules held together by van der Waals forces, and (iii) an archetypal ionic compound KCl. The charge balance rule, assigning classical charges of "+1" to K and "-1" to Cl, predicts that no compounds other than KCl are possible. However, our quantum-mechanical variable-composition evolutionary simulations predict an extremely complex phase diagram, with new thermodynamically stable compounds K3Cl, K2Cl, K3Cl2, K4Cl3, K5Cl4, K3Cl5, KCl3 and KCl7. Of particular interest are 2D-metallic homologs Kn+1 Cln, the presence of positively charged Cl atoms in KCl7, and the predicted stability of KCl3 already at nearly ambient pressures at zero Kelvin. We have synthesized cubic -KCl3 at 40-70 GPa and trigonal -KCl3 at 20-40 GPa in a laser-heated diamond anvil cell (DAC) at temperature exceeding 2000 K from KCl and Cl2. These phases were identified using in situ synchrotron X-ray diffraction and Raman spectroscopy. Upon unloading to 10 GPa, -KCl3 transforms to a yet unknown structure before final decomposition to KCl and Cl2 at near-ambient conditions.
AB - K-Cl is a simple system displaying all four main types of bonding, as it contains (i) metallic potassium, (ii) elemental chlorine made of covalently bonded Cl 2 molecules held together by van der Waals forces, and (iii) an archetypal ionic compound KCl. The charge balance rule, assigning classical charges of "+1" to K and "-1" to Cl, predicts that no compounds other than KCl are possible. However, our quantum-mechanical variable-composition evolutionary simulations predict an extremely complex phase diagram, with new thermodynamically stable compounds K3Cl, K2Cl, K3Cl2, K4Cl3, K5Cl4, K3Cl5, KCl3 and KCl7. Of particular interest are 2D-metallic homologs Kn+1 Cln, the presence of positively charged Cl atoms in KCl7, and the predicted stability of KCl3 already at nearly ambient pressures at zero Kelvin. We have synthesized cubic -KCl3 at 40-70 GPa and trigonal -KCl3 at 20-40 GPa in a laser-heated diamond anvil cell (DAC) at temperature exceeding 2000 K from KCl and Cl2. These phases were identified using in situ synchrotron X-ray diffraction and Raman spectroscopy. Upon unloading to 10 GPa, -KCl3 transforms to a yet unknown structure before final decomposition to KCl and Cl2 at near-ambient conditions.
UR - http://www.scopus.com/inward/record.url?scp=84970005638&partnerID=8YFLogxK
U2 - 10.1038/srep26265
DO - 10.1038/srep26265
M3 - 文章
AN - SCOPUS:84970005638
SN - 2045-2322
VL - 6
JO - Scientific Reports
JF - Scientific Reports
M1 - 26265
ER -