A polyhydride or superhydride is a compound that contains an abnormally large amount of hydrogen. This can be described as high hydrogen stoichiometry. Examples include iron pentahydride FeH5, LiH6, and LiH7. By contrast, the more well known lithium hydride only has one hydrogen atom.[1]

Polyhydrides are only known to be stable under high pressure.[1]

Polyhydrides are important because they can form substances with a very high density of hydrogen. They may resemble the elusive metallic hydrogen, but can be made under lower pressures. One possibility is that they could be superconductors. Hydrogen sulfide under high pressures forms SH3 units, and can be a superconductor at 203 K (−70 °C) and a pressure of 1.5 million atmospheres.[1]


Unit cell diagram showing the structure of NaH7, which contains H3 complexes. The coloured balls it the isosurface, plotted at the level of 0.07 electrons*Å−3. One of H2 molecules is bonded to a hydrogen atom in the NaH unit with a bond length of 1.25 Å, forming a H3 linear anion.

The polyhydrides of alkaline earth and alkali metals contain cage structures. Also hydrogen may be clustered into H, H3, or H2 units. Polyhydrides of transition metals may have the hydrogen atoms arranged around the metal atom. Computations suggest that increasing hydrogen levels will reduce the dimensionality of the metal arrangement, so that layers form separated by hydrogen sheets.[1] The H3 substructure is linear.[2]

H3+ would form triangular structures in the hypothetical H5Cl.[2]


When sodium hydride is compressed with hydrogen, NaH3 and NaH7 form. These are formed at 30 GPa and 2,100 K.[2]

Heating and compressing a metal with ammonia borane avoids using bulky hydrogen, and produces boron nitride as a decomposition product in addition to the polyhydride.[3]

formula name temperature




crystal structure space group a Å b c β cell volume formulae

per unit cell

Tc K Comment refs
LiH2 lithium dihydride 27 130 [4]
LiH6 Lithium hexahydride [1]
LiH7 Lithium heptahydride [1]
NaH3 sodium trihydride orthorhombic Cmcm 3.332 Å 6.354 Å 4.142 Å 90 87.69 4 [2]
NaH7 sodium heptahydride monoclinic Cc 6.99 3.597 5.541 69.465 130.5 [2]
CaHx 500 22 double hexagon [5]
CaHx 600 121 [5]
SrH6 pseudo cubic Pm3m semiconductor

metallize > 220 GPa

Sr3H13 C2/m [6]
SrH22 138 triclinic P1 [6]
BaH12 Barium dodecahydride 75 pseudo cubic 5.43 5.41 5.37 39.48 20K [7][8]
FeH5 iron pentahydride 1200 66 tetragonal I4/mmm [1]
H3S Sulfur trihydride 25 150 cubic Im3m 203K [9]
H3Se Selenium trihydride 10 [10]
YH4 yttrium tetrahydride 700 160 I4/mmm [11]
YH6 yttrium hexahydride 700 160 Im-3m 224 [11][12][13]
YH9 yttrium nonahydride 400 237 P63/mmc 243 [11]
LaH10 Lanthanum decahydride 1000 170 cubic Fm3m 5.09 5.09 5.09 132 4 250K [14][15]
LaH10 Lanthanum decahydride 25 121 Hexagonal R3m 3.67 3.67 8.83 1 [14]
LaD11 Lanthanum undecahydride 2150 130-160 Tetragonal P4/nmm 168 [15]
LaH12 Lanthanum dodecahydride Cubic insulating [15]
LaH7 Lanthanum heptahydride 25 109 monoclinic C2/m 6.44 3.8 3.69 135 63.9 2 [14]
CeH9 Cerium nonahydride 93 hexagonal P63/mmc 3.711 5.543 33.053 100K [16]
CeH10 Cerium decahydride Fm3m 115K [17]
PrH9 Praseodymium nonahydride 90-140 P63/mmc 3.60 5.47 61.5 55K 9K [18][19]
PrH9 Praseodymium nonahydride 120 F43m 4.98 124 69K [18]
NdH4 Neodymium tetrahydride 85-135 tetragonal I4/mmm 2.8234 5,7808 [20]
NdH7 Neodymium heptahydride 85-135 monoclinic C2/c 3.3177 6.252 5.707 89.354 [20]
NdH9 Neodymium nonahydride 110-130 hexagonal P63/mmc 3.458 5.935 [20]
EuH4 50-130 I4/mmm [21]
Eu8H46 1600 130 cubic Pm3n 5.865 [21]
EuH9 Europium nonahydride 86-130 cubic F43m [21]
EuH9 Europium nonahydride >130 hexagonal P63/mmc [21]
ThH4 Thorium tetrahydride 86 I4/mmm 2.903 4.421 57.23 2 [3]
ThH4 Thorium tetrahydride 88 trigonal P321 5.500 3.29 86.18 [3]
ThH4 Thorium tetrahydride orthorhombic Fmmm [3]
ThH6 Thorium hexahydride 86-104 Cmc21 32.36 [3]
ThH9 Thorium nonahydride 2100 152 hexagonal P63/mmc 3.713 5.541 66.20 [3]
ThH10 Thorium decahydride 1800 85-185 cubic Fm3m 5.29 148.0 161 [3]
ThH10 Thorium decahydride <85 Immm 5.304 3.287 3.647 74.03 [3]
UH7 Uranium heptahydride 2000 63 fcc P63/mmc [22]
UH8 Uranium octahydride 300 1-55 fcc Fm3m [22]
UH9 Uranium nonahydride 40-55 fcc P63/mmc [22]


Using computational chemistry many other polyhydrides are predicted, including LiH8,[23] LiH9,[24] LiH10,[24] CsH3,[25] KH5 RbH5,[26] RbH9,[23] NaH9, BaH6,[26] CaH6,[27] MgH4, MgH12, MgH16,[28] SrH4,[29] SrH10, SrH12,[23] ScH4, ScH6, ScH8,[30] YH4 and YH6,[31] YH24, LaH8, LaH10,[32] YH9, LaH11, CeH8, CeH9, CeH10,[33] PrH8, PrH9,[34] ThH6, ThH7 and ThH10,[35] U2H13, UH7, UH8, UH9,[22] AlH5,[36] GaH5, InH5,[23] SnH8, SnH12, SnH14,[37] PbH8,[38] SiH8 (subsequently discovered),[23] GeH8,[39] (although Ge3H11 may be stable instead)[40] AsH8, SbH4,[41] BiH4, BiH5, BiH6,[42] H3Se,[43] H3S,[44] Te2H5, TeH4,[45] PoH4, PoH6,[23] H2F, H3F,[23] H2Cl, H3Cl, H5Cl, H7Cl,[46] H2Br, H3Br, H4Br, H5Br, H5I,[23] XeH2, XeH4,.[47]

Among the transition elements, VH8 in a C2/m structure around 200 GPa is predicted to have a superconducting transition temperature of 71.4 K. VH5 in a P63/mmm space group has a lower transition temperature.[48]



Under suitably high pressures polyhydrides may become superconducting. Characteristics of substances that are predicted to have high superconducting temperatures are a high phonon frequency, which will happen for light elements, and strong bonds. Hydrogen is the lightest and so will have the highest frequency of vibration. Even changing the isotope to deuterium will lower the frequency and lower the transition temperature. Compounds with more hydrogen will resemble the predicted metallic hydrogen. However, superconductors also tend to be substances with high symmetry and also need the electrons not to be locked into molecular subunits, and require large numbers of electrons in states near the Fermi level. There should also be electron-phonon coupling which happens when the electric properties are tied to the mechanical position of the hydrogen atoms.[34][49][50] The highest superconduction critical temperatures are predicted to be in groups 3 and 3 of the periodic table. Late transitions elements, heavy lanthanides or actinides have extra d- or f-electrons that interfere with superconductivity.[51]

For example, lithium hexahydride is predicted to lose all electrical resistance below 38 K at a pressure of 150 GPa. The hypothetical LiH8 has a predicted superconducting transition temperature at 31 K at 200 GPa.[52] MgH6 is predicted to have a Tc of 400 K around 300 GPa.[53] CaH6 could have a Tc of 260 K at 120 GPa. PH3 doped H3S is also predicted to have a transition temperature above the 203 K measured for H3S (contaminated with solid sulfur).[54] Rare earth and actinide polyhydrides may also have highish transition temperatures, for example, ThH10 with Tc = 241 K.[35] UH8, which can be decompressed to room temperature without decomposition, is predicted to have a transition temperature of 193 K.[35] AcH10, if it could be ever made, is predicted to superconduct at temperatures over 204 K, and AcH10 would be similarly conducting under lower pressures (150 GPa).[55]

H3Se actually is a van der Waals solid with formula 2H2Se•H2 with a measured Tc of 105 K under a pressure of 135 GPa.[10]

Ternary superhydridesEdit

Ternary superhydrides open up the possibility of many more formulas.[56] For example, a carbonaceous sulfur hydride is a superconductor up to 15 °C (approaching room temperature)[57] and Li2MgH16 may also be superconducting at high temperatures (200 °C).[58] A compound of lanthanum, boron and hydrogen is speculated to be a "hot" superconductor (550K).[59][60] Elements may substitute for others and so modify the properties eg (La,Y)H6 and (La,Y)H10 can be made to have a slightly higher critical temperature than YH6 or LaH10.[61]

See alsoEdit


  1. ^ a b c d e f g Pépin, C. M.; Geneste, G.; Dewaele, A.; Mezouar, M.; Loubeyre, P. (27 July 2017). "Synthesis of FeH5 : A layered structure with atomic hydrogen slabs". Science. 357 (6349): 382–385. Bibcode:2017Sci...357..382P. doi:10.1126/science.aan0961. PMID 28751605.
  2. ^ a b c d e Struzhkin, Viktor V.; Kim, Duck Young; Stavrou, Elissaios; Muramatsu, Takaki; Mao, Ho-kwang; Pickard, Chris J.; Needs, Richard J.; Prakapenka, Vitali B.; Goncharov, Alexander F. (28 July 2016). "Synthesis of sodium polyhydrides at high pressures". Nature Communications. 7: 12267. Bibcode:2016NatCo...712267S. doi:10.1038/ncomms12267. PMC 4974473. PMID 27464650.
  3. ^ a b c d e f g h Semenok, D. V.; Kvashnin, A. G; Ivanova, A. G.; Troayn, I. A.; Oganov, A. R. (2019). "Synthesis of ThH4 , ThH6 , ThH9 and ThH10 : a route to room-temperature superconductivity". doi:10.13140/RG.2.2.31274.88003. {{cite journal}}: Cite journal requires |journal= (help)
  4. ^ Pépin, Charles; Loubeyre, Paul; Occelli, Florent; Dumas, Paul (23 June 2015). "Synthesis of lithium polyhydrides above 130 GPa at 300 K". Proceedings of the National Academy of Sciences. 112 (25): 7673–7676. Bibcode:2015PNAS..112.7673P. doi:10.1073/pnas.1507508112. PMC 4485130. PMID 26056306.
  5. ^ a b Mishra, Ajay Kumar; Ahart, Muhtar; Somayazulu, Maddury; Park, C. Y; Hemley, Russel J (2017-03-13). "Synthesis of Calcium polyhydrides at high pressure and high temperature". Bulletin of the American Physical Society. 62 (4): B35.008. Bibcode:2017APS..MARB35008M.
  6. ^ a b c Semenok, Dmitrii V.; Chen, Wuhao; Huang, Xiaoli; Zhou, Di; Kruglov, Ivan A.; Mazitov, Arslan B.; Galasso, Michele; Tantardini, Christian; Gonze, Xavier; Kvashnin, Alexander G.; Oganov, Artem R. (2022-06-03). "Sr‐Doped Superionic Hydrogen Glass: Synthesis and Properties of SrH 22". Advanced Materials. 34 (27): 2200924. arXiv:2110.15628. doi:10.1002/adma.202200924. ISSN 0935-9648. S2CID 240288572.
  7. ^ chen, Wuhao (April 2020). "High-Pressure Synthesis of Barium Superhydrides: Pseudocubic BaH12". ResearchGate. Retrieved 2020-04-28.
  8. ^ Chen, Wuhao; Semenok, Dmitrii V.; Kvashnin, Alexander G.; Huang, Xiaoli; Kruglov, Ivan A.; Galasso, Michele; Song, Hao; Duan, Defang; Goncharov, Alexander F.; Prakapenka, Vitali B.; Oganov, Artem R.; Cui, Tian (December 2021). "Synthesis of molecular metallic barium superhydride: pseudocubic BaH12". Nature Communications. 12 (1): 273. arXiv:2004.12294. Bibcode:2021NatCo..12..273C. doi:10.1038/s41467-020-20103-5. PMC 7801595. PMID 33431840.
  9. ^ Shylin, S. I.; Ksenofontov, V.; Troyan, I. A.; Eremets, M. I.; Drozdov, A. P. (September 2015). "Conventional superconductivity at 203 kelvin at high pressures in the sulfur hydride system". Nature. 525 (7567): 73–76. arXiv:1506.08190. Bibcode:2015Natur.525...73D. doi:10.1038/nature14964. ISSN 1476-4687. PMID 26280333. S2CID 4468914.
  10. ^ a b Mishra, A. K.; Somayazulu, M.; Ahart, M.; Karandikar, A.; Hemley, R. J.; Struzhkin, V. (9 March 2018). "Novel Synthesis Route and Observation of Superconductivity in the Se-H System at Extreme Conditions". APS March Meeting Abstracts. 63 (1): X38.008. Bibcode:2018APS..MARX38008M.
  11. ^ a b c Kong, P. P.; Minkov, V. S.; Kuzovnikov, M. A.; Besedin, S. P.; Drozdov, A. P.; Mozaffari, S.; Balicas, L.; Balakirev, F. F.; Prakapenka, V. B.; Greenberg, E.; Knyazev, D. A. (2019-09-23). "Superconductivity up to 243 K in yttrium hydrides under high pressure". arXiv:1909.10482 [cond-mat.supr-con].
  12. ^ Troyan, I. A.; Semenok, D. V.; Kvashnin, A. G.; Ivanova, A. G.; Prakapenka, V. B.; Greenberg, E.; Gavriliuk, A. G.; Lyubutin, I. S.; Struzhkin, V. V.; Oganov, A. R. (2021). "Anomalous High‐Temperature Superconductivity in YH 6". Advanced Materials. 33 (15): e2006832. arXiv:1908.01534. doi:10.1002/adma.202006832. ISSN 0935-9648. PMID 33751670. S2CID 219636252.
  13. ^ Troyan, Ivan A.; Semenok, Dmitrii V.; Kvashnin, Alexander G.; Sadakov, Andrey V.; Sobolevskiy, Oleg A.; Pudalov, Vladimir M.; Ivanova, Anna G.; Prakapenka, Vitali B.; Greenberg, Eran; Gavriliuk, Alexander G.; Lyubutin, Igor S.; Struzhkin, Viktor V.; Bergara, Aitor; Errea, Ion; Bianco, Raffaello; Calandra, Matteo; Mauri, Francesco; Monacelli, Lorenzo; Akashi, Ryosuke; Oganov, Artem R. (10 March 2021). "Anomalous High‐Temperature Superconductivity in YH 6". Advanced Materials. 33 (15): 2006832. arXiv:1908.01534. doi:10.1002/adma.202006832. ISSN 0935-9648. PMID 33751670. S2CID 219636252.
  14. ^ a b c Geballe, Zachary M.; Liu, Hanyu; Mishra, Ajay K.; Ahart, Muhtar; Somayazulu, Maddury; Meng, Yue; Baldini, Maria; Hemley, Russell J. (15 January 2018). "Synthesis and Stability of Lanthanum Superhydrides". Angewandte Chemie International Edition. 57 (3): 688–692. Bibcode:2018APS..MARX38010G. doi:10.1002/anie.201709970. PMID 29193506.
  15. ^ a b c Drozdov, A. P.; Kong, P. P.; Minkov, V. S.; Besedin, S. P.; Kuzovnikov, M. A.; Mozaffari, S.; Balicas, L.; Balakirev, F. F.; Graf, D. E.; Prakapenka, V. B.; Greenberg, E.; Knyazev, D. A.; Tkacz, M.; Eremets, M. I. (22 May 2019). "Superconductivity at 250 K in lanthanum hydride under high pressures". Nature. 569 (7757): 528–531. arXiv:1812.01561. Bibcode:2019Natur.569..528D. doi:10.1038/s41586-019-1201-8. PMID 31118520. S2CID 119231000.
  16. ^ Salke, Nilesh P. (May 2018). "Synthesis of clathrate cerium superhydride CeH9 below 100 GPa with atomic hydrogen sublattice". Nature Communications. 10 (1): 4453. arXiv:1805.02060. doi:10.1038/s41467-019-12326-y. PMC 6773858. PMID 31575861.
  17. ^ Chen, Wuhao; Semenok, Dmitrii V.; Huang, Xiaoli; Shu, Haiyun; Li, Xin; Duan, Defang; Cui, Tian; Oganov, Artem R. (2021-09-09). "High-Temperature Superconducting Phases in Cerium Superhydride with a T c up to 115 K below a Pressure of 1 Megabar". Physical Review Letters. 127 (11): 117001. arXiv:2101.01315. Bibcode:2021PhRvL.127k7001C. doi:10.1103/PhysRevLett.127.117001. ISSN 0031-9007. PMID 34558917. S2CID 230524009.
  18. ^ a b Zhou, Di; Semenok, Dmitrii; Defang Duan; Xie, Hui; Xiaoli Huang; Wuhao Chen; Li, Xin; Bingbing Liu; Oganov, Artem R (2019). "Superconducting Praseodymium Superhydrides". Unpublished. 6 (9): eaax6849. arXiv:1904.06643. doi:10.1126/sciadv.aax6849. PMC 7048426. PMID 32158937.
  19. ^ Zhou, Di; Semenok, Dmitrii V.; Duan, Defang; Xie, Hui; Chen, Wuhao; Huang, Xiaoli; Li, Xin; Liu, Bingbing; Oganov, Artem R.; Cui, Tian (February 2020). "Superconducting praseodymium superhydrides". Science Advances. 6 (9): eaax6849. arXiv:1904.06643. Bibcode:2020SciA....6.6849Z. doi:10.1126/sciadv.aax6849. ISSN 2375-2548. PMC 7048426. PMID 32158937.
  20. ^ a b c Zhou, Di; Semenok, Dmitrii V.; Xie, Hui; Huang, Xiaoli; Duan, Defang; Aperis, Alex; Oppeneer, Peter M.; Galasso, Michele; Kartsev, Alexey I.; Kvashnin, Alexander G.; Oganov, Artem R. (2020-02-12). "High-Pressure Synthesis of Magnetic Neodymium Polyhydrides". Journal of the American Chemical Society. 142 (6): 2803–2811. arXiv:1908.08304. doi:10.1021/jacs.9b10439. ISSN 0002-7863. PMID 31967807. S2CID 201330599.
  21. ^ a b c d Semenok, Dmitrii V.; Zhou, Di; Kvashnin, Alexander G.; Huang, Xiaoli; Galasso, Michele; Kruglov, Ivan A.; Ivanova, Anna G.; Gavriliuk, Alexander G.; Chen, Wuhao; Tkachenko, Nikolay V.; Boldyrev, Alexander I. (2020-12-09). "Novel Strongly Correlated Europium Superhydrides". The Journal of Physical Chemistry Letters. 12 (1): 32–40. arXiv:2012.05595. doi:10.1021/acs.jpclett.0c03331. ISSN 1948-7185. PMID 33296213. S2CID 228084018.
  22. ^ a b c d Kruglov, Ivan A.; Kvashnin, Alexander G.; Goncharov, Alexander F.; Oganov, Artem R.; Lobanov, Sergey; Holtgrewe, Nicholas; Yanilkin, Alexey V. (17 August 2017). "High-temperature superconductivity of uranium hydrides at near-ambient conditions". arXiv:1708.05251 [cond-mat.mtrl-sci].
  23. ^ a b c d e f g h Duan, Defang; Liu, Yunxian; Ma, Yanbin; Shao, Ziji; Liu, Bingbing; Cui, Tian (28 April 2016). "Structure and superconductivity of hydrides at high pressures". National Science Review. 4: 121–135. doi:10.1093/nsr/nww029.
  24. ^ a b Chen, Yangmei; Geng, Hua Y.; Yan, Xiaozhen; Sun, Yi; Wu, Qiang; Chen, Xiangrong (2017). "Prediction of Stable Ground-State Lithium Polyhydrides under High Pressures". Inorganic Chemistry. 56 (7): 3867–3874. arXiv:1705.04199. doi:10.1021/acs.inorgchem.6b02709. PMID 28318270. S2CID 21976165.
  25. ^ Shamp, Andrew; Hooper, James; Zurek, Eva (3 September 2012). "Compressed Cesium Polyhydrides: Cs+ Sublattices and H3- Three-Connected Nets". Inorganic Chemistry. 51 (17): 9333–9342. doi:10.1021/ic301045v. PMID 22897718.
  26. ^ a b Zurek, Eva (6 June 2016). "Hydrides of the Alkali Metals and Alkaline Earth Metals Under Pressure". Comments on Inorganic Chemistry. 37 (2): 78–98. doi:10.1080/02603594.2016.1196679. S2CID 99251100.
  27. ^ Wang, H.; Tse, J. S.; Tanaka, K.; Iitaka, T.; Ma, Y. (6 April 2012). "Superconductive sodalite-like clathrate calcium hydride at high pressures". Proceedings of the National Academy of Sciences. 109 (17): 6463–6466. arXiv:1203.0263. Bibcode:2012PNAS..109.6463W. doi:10.1073/pnas.1118168109. PMC 3340045. PMID 22492976.
  28. ^ Lonie, David C.; Hooper, James; Altintas, Bahadir; Zurek, Eva (19 February 2013). "Metallization of magnesium polyhydrides under pressure". Physical Review B. 87 (5): 054107. arXiv:1301.4750. Bibcode:2013PhRvB..87e4107L. doi:10.1103/PhysRevB.87.054107. S2CID 85453835.
  29. ^ Hooper, James; Terpstra, Tyson; Shamp, Andrew; Zurek, Eva (27 March 2014). "Composition and Constitution of Compressed Strontium Polyhydrides". The Journal of Physical Chemistry C. 118 (12): 6433–6447. doi:10.1021/jp4125342.
  30. ^ Qian, Shifeng (2017). "Theoretical study of stability and superconductivity of". Physical Review B. 96 (9): 094513. Bibcode:2017PhRvB..96i4513Q. doi:10.1103/physrevb.96.094513.
  31. ^ Li, Yinwei; Hao, Jian; Liu, Hanyu; Tse, John S.; Wang, Yanchao; Ma, Yanming (5 May 2015). "Pressure-stabilized superconductive yttrium hydrides". Scientific Reports. 5 (1): 9948. Bibcode:2015NatSR...5E9948L. doi:10.1038/srep09948. PMC 4419593. PMID 25942452.
  32. ^ Liu, Hanyu; Naumov, Ivan I.; Hoffmann, Roald; Ashcroft, N. W.; Hemley, Russell J. (3 July 2017). "Potential high-Tc superconducting lanthanum and yttrium hydrides at high pressure". Proceedings of the National Academy of Sciences. 114 (27): 6990–6995. Bibcode:2017PNAS..114.6990L. doi:10.1073/pnas.1704505114. PMC 5502634. PMID 28630301.
  33. ^ Tsuppayakorn-aek, Prutthipong; Pinsook, Udomsilp; Luo, Wei; Ahuja, Rajeev; Bovornratanaraks, Thiti (12 August 2020). "Superconductivity of Superhydride CeH10 under High Pressure". Materials Research Express. 7 (8): 086001. Bibcode:2020MRE.....7h6001T. doi:10.1088/2053-1591/ababc2. S2CID 225379054.
  34. ^ a b Peng, Feng; Sun, Ying; Pickard, Chris J.; Needs, Richard J.; Wu, Qiang; Ma, Yanming (8 September 2017). "Hydrogen Clathrate Structures in Rare Earth Hydrides at High Pressures: Possible Route to Room-Temperature Superconductivity" (PDF). Physical Review Letters. 119 (10): 107001. Bibcode:2017PhRvL.119j7001P. doi:10.1103/PhysRevLett.119.107001. PMID 28949166.
  35. ^ a b c Kvashnin, Alexander G.; Semenok, Dmitry V.; Kruglov, Ivan A.; Oganov, Artem R. (November 2017). "High-Temperature Superconductivity in Th-H System at Pressure Conditions". arXiv:1711.00278. doi:10.1021/acsami.8b17100.
  36. ^ Hou, Pugeng; Zhao, Xiusong; Tian, Fubo; Li, Da; Duan, Defang; Zhao, Zhonglong; Chu, Binhua; Liu, Bingbing; Cui, Tian (2015). "High pressure structures and superconductivity of AlH3(H2) predicted by first principles". RSC Adv. 5 (7): 5096–5101. Bibcode:2015RSCAd...5.5096H. doi:10.1039/C4RA14990D. S2CID 97440127.
  37. ^ Mahdi Davari Esfahani, M.; Wang, Zhenhai; Oganov, Artem R.; Dong, Huafeng; Zhu, Qiang; Wang, Shengnan; Rakitin, Maksim S.; Zhou, Xiang-Feng (11 March 2016). "Superconductivity of novel tin hydrides (Snn Hm) under pressure". Scientific Reports. 6 (1): 22873. arXiv:1512.07604. Bibcode:2016NatSR...622873M. doi:10.1038/srep22873. PMC 4786816. PMID 26964636.
  38. ^ Cheng, Ya; Zhang, Chao; Wang, Tingting; Zhong, Guohua; Yang, Chunlei; Chen, Xiao-Jia; Lin, Hai-Qing (12 November 2015). "Pressure-induced superconductivity in H2-containing hydride PbH4(H2)2". Scientific Reports. 5 (1): 16475. Bibcode:2015NatSR...516475C. doi:10.1038/srep16475. PMC 4642309. PMID 26559369.
  39. ^ Szcze¸śniak, R.; Szcze¸śniak, D.; Durajski, A.P. (April 2014). "Thermodynamics of the superconducting phase in compressed GeH4(H2)2". Solid State Communications. 184: 6–11. Bibcode:2014SSCom.184....6S. doi:10.1016/j.ssc.2013.12.036.
  40. ^ Davari Esfahani, M. Mahdi; Oganov, Artem R.; Niu, Haiyang; Zhang, Jin (10 April 2017). "Superconductivity and unexpected chemistry of germanium hydrides under pressure". Physical Review B. 95 (13): 134506. arXiv:1701.05600. Bibcode:2017PhRvB..95m4506D. doi:10.1103/PhysRevB.95.134506. S2CID 43481894.
  41. ^ Fu, Yuhao; Du, Xiangpo; Zhang, Lijun; Peng, Feng; Zhang, Miao; Pickard, Chris J.; Needs, Richard J.; Singh, David J.; Zheng, Weitao; Ma, Yanming (22 March 2016). "High-Pressure Phase Stability and Superconductivity of Pnictogen Hydrides and Chemical Trends for Compressed Hydrides". Chemistry of Materials. 28 (6): 1746–1755. arXiv:1510.04415. doi:10.1021/acs.chemmater.5b04638. S2CID 54571045.
  42. ^ Ma, Yanbin; Duan, Defang; Li, Da; Liu, Yunxian; Tian, Fubo; Yu, Hongyu; Xu, Chunhong; Shao, Ziji; Liu, Bingbing; Cui, Tian (17 November 2015). "High-pressure structures and superconductivity of bismuth hydrides". arXiv:1511.05291 [cond-mat.supr-con].
  43. ^ Zhang, Shoutao; Wang, Yanchao; Zhang, Jurong; Liu, Hanyu; Zhong, Xin; Song, Hai-Feng; Yang, Guochun; Zhang, Lijun; Ma, Yanming (22 October 2015). "Phase Diagram and High-Temperature Superconductivity of Compressed Selenium Hydrides". Scientific Reports. 5 (1): 15433. arXiv:1502.02607. Bibcode:2015NatSR...515433Z. doi:10.1038/srep15433. PMC 4614537. PMID 26490223.
  44. ^ Durajski, Artur P.; Szczęśniak, Radosław (30 June 2017). "First-principles study of superconducting hydrogen sulfide at pressure up to 500 GPa". Scientific Reports. 7 (1): 4473. Bibcode:2017NatSR...7.4473D. doi:10.1038/s41598-017-04714-5. PMC 5493702. PMID 28667259.
  45. ^ Zhong, Xin; Wang, Hui; Zhang, Jurong; Liu, Hanyu; Zhang, Shoutao; Song, Hai-Feng; Yang, Guochun; Zhang, Lijun; Ma, Yanming (4 February 2016). "Tellurium Hydrides at High Pressures: High-Temperature Superconductors". Physical Review Letters. 116 (5): 057002. arXiv:1503.00396. Bibcode:2016PhRvL.116e7002Z. doi:10.1103/PhysRevLett.116.057002. PMID 26894729. S2CID 14435357.
  46. ^ Duan, Defang; Huang, Xiaoli; Tian, Fubo; Liu, Yunxian; Li, Da; Yu, Hongyu; Liu, Bingbing; Tian, Wenjing; Cui, Tian (12 November 2015). "Predicted Formation of H3+ in Solid Halogen Polyhydrides at High Pressures". The Journal of Physical Chemistry A. 119 (45): 11059–11065. Bibcode:2015JPCA..11911059D. doi:10.1021/acs.jpca.5b08183. PMID 26469181.
  47. ^ Yan, Xiaozhen; Chen, Yangmei; Kuang, Xiaoyu; Xiang, Shikai (28 September 2015). "Structure, stability, and superconductivity of new Xe–H compounds under high pressure". The Journal of Chemical Physics. 143 (12): 124310. Bibcode:2015JChPh.143l4310Y. doi:10.1063/1.4931931. PMID 26429014.
  48. ^ Li, Xiaofeng; Peng, Feng (2 November 2017). "Superconductivity of Pressure-Stabilized Vanadium Hydrides". Inorganic Chemistry. 56 (22): 13759–13765. doi:10.1021/acs.inorgchem.7b01686. PMID 29094931.
  49. ^ Pietronero, Luciano; Boeri, Lilia; Cappelluti, Emmanuele; Ortenzi, Luciano (9 September 2017). "Conventional/unconventional superconductivity in high-pressure hydrides and beyond: insights from theory and perspectives". Quantum Studies: Mathematics and Foundations. 5: 5–21. doi:10.1007/s40509-017-0128-8. hdl:11573/1622515. S2CID 139800480.
  50. ^ Pinsook, Udomsilp (July 2020). "In search for near-room-temperature superconducting critical temperature of metal superhydrides under high pressure: A review". Journal of Metals, Materials and Minerals. 30: 31. doi:10.14456/jmmm.2020.18.
  51. ^ Semenok, Dmitrii V.; Kruglov, Ivan A.; Savkin, Igor A.; Kvashnin, Alexander G.; Oganov, Artem R. (April 2020). "On Distribution of Superconductivity in Metal Hydrides". Current Opinion in Solid State and Materials Science. 24 (2): 100808. arXiv:1806.00865. Bibcode:2020COSSM..24j0808S. doi:10.1016/j.cossms.2020.100808. S2CID 119433896.
  52. ^ Xie, Yu; Li, Quan; Oganov, Artem R.; Wang, Hui (31 January 2014). "Superconductivity of lithium-doped hydrogen under high pressure". Acta Crystallographica Section C. 70 (2): 104–111. doi:10.1107/S2053229613028337. PMID 24508954.
  53. ^ Szczȩśniak, R.; Durajski, A. P. (13 July 2016). "Superconductivity well above room temperature in compressed MgH6". Frontiers of Physics. 11 (6): 117406. Bibcode:2016FrPhy..11k7406S. doi:10.1007/s11467-016-0578-1. S2CID 124245616.
  54. ^ Eremets, M I; Drozdov, A P (30 November 2016). "High-temperature conventional superconductivity". Physics-Uspekhi. 59 (11): 1154–1160. Bibcode:2016PhyU...59.1154E. doi:10.3367/UFNe.2016.09.037921.
  55. ^ Semenok, Dmitrii V; Kvashnin, Alexander G; Kruglov, Ivan A; Oganov, Artem R (2018). "Actinium hydrides AcH10, AcH12, AcH16 as high-temperature conventional superconductors". The Journal of Physical Chemistry Letters. 9 (8): 1920–1926. arXiv:1802.05676. doi:10.1021/acs.jpclett.8b00615. PMID 29589444. S2CID 4620593.
  56. ^ Sukmas, Wiwittawin; Tsuppayakorn-aek, Prutthipong; Pinsook, Udomsilp; Bovornratanaraks, Thiti (30 December 2020). "Near-room-temperature superconductivity of Mg/Ca substituted metal hexahydride under pressure". Journal of Alloys and Compounds. 849: 156434. doi:10.1016/j.jallcom.2020.156434. S2CID 225031775.
  57. ^ Castelvecchi, Davide (15 October 2020). "First room-temperature superconductor excites — and baffles — scientists". Nature. 586 (7829): 349. Bibcode:2020Natur.586..349C. doi:10.1038/d41586-020-02895-0. PMID 33057238.
  58. ^ Flores-Livas, José A.; Arita, Ryotaro (26 August 2019). "A Prediction for "Hot" Superconductivity". Physics. 12: 96. Bibcode:2019PhyOJ..12...96F. doi:10.1103/Physics.12.96.
  59. ^ Grockowiak, A. D.; Ahart, M.; Helm, T.; Coniglio, W. A.; Kumar, R.; Somayazulu, M.; Meng, Y.; Oliff, M.; Williams, V.; Ashcroft, N. W.; Hemley, R. J.; Tozer, S. W. (2022). "Hot Hydride Superconductivity Above 550 K". Frontiers in Electronic Materials. 2. arXiv:2006.03004. doi:10.3389/femat.2022.837651.
  60. ^ Di Cataldo, Simone; von der Linden, Wolfgang; Boeri, Lilia (2021-06-14). "La-$X$-H hydrides: is hot superconductivity possible?". arXiv:2106.07266 [cond-mat.supr-con].
  61. ^ Semenok, Dmitrii V.; Troyan, Ivan A.; Ivanova, Anna G.; Kvashnin, Alexander G.; Kruglov, Ivan A.; Hanfland, Michael; Sadakov, Andrey V.; Sobolevskiy, Oleg A.; Pervakov, Kirill S.; Lyubutin, Igor S.; Glazyrin, Konstantin V.; Giordano, Nico; Karimov, Denis N.; Vasiliev, Alexander L.; Akashi, Ryosuke; Pudalov, Vladimir M.; Oganov, Artem R. (July 2021). "Superconductivity at 253 K in lanthanum–yttrium ternary hydrides". Materials Today: S1369702121001309. arXiv:2012.04787. doi:10.1016/j.mattod.2021.03.025. S2CID 228064078.