Herbertsmithite
| Herbertsmithite | |
|---|---|
 Herbertsmithite from Caracoles, Sierra Gorda District, Tocopilla Province, Chile (size: 4.5 × 4.4 × 2.7 cm) | |
| General | |
| Category | Halide mineral |
| Formula (repeating unit) | ZnCu3(OH)6Cl2 |
| IMA symbol | Her[1] |
| Strunz classification | 3.DA.10c |
| Crystal system | Trigonal |
| Crystal class | Hexagonal scalenohedral (3m) H-M symbol: (3 2/m) |
| Space group | R3m |
| Unit cell | a = 6.834 Å c = 14.075 Å; Z = 3 |
| Identification | |
| Color | Light green, blue-green |
| Crystal habit | Aggregates of rhombohedral crystals |
| Cleavage | Good on {1011} |
| Tenacity | Brittle |
| Mohs scale hardness | 3–3.5 |
| Luster | Vitreous to adamantine |
| Streak | Light green |
| Diaphaneity | Transparent |
| Specific gravity | 3.75–3.95 |
| Optical properties | Uniaxial (−) |
| Refractive index | nε 1.817, nω 1.825 |
| Birefringence | 0.0080 |
| References | [2][3] |
Herbertsmithite is a rhombohedral green-coloured mineral with chemical formula ZnCu3(OH)6Cl2. It is named after the mineralogist Herbert Smith (1872–1953) and was first found in 1972 in Chile. It is polymorphous with kapellasite and closely related to paratacamite. Herbertsmithite has also been found near Anarak, Iran, hence its other name, anarakite.[4]
Herbertsmithite is associated with copper mineralization in syenitic porphyries and granites in Chile and in Triassic dolomite formations in Iran. It has also been reported from the Osborn District in the Big Horn Mountains of Maricopa County, Arizona and the Lavrion District Mines of Attica, Greece.[2]
Herbertsmithite has a vitreous luster and is fairly transparent with a light-green to blue green color. Herbertsmithite has a Mohs hardness of between 3 and 3.5. The crystal's density is 3.95 g/cm3.[4]
In 2012, the pure synthetic form of herbertsmithite was discovered to be able to exhibit the properties of a quantum spin liquid,[5] due to its Kagome lattice structure.[6] Herbertsmithite is the first mineral known to exhibit this unique state of magnetism: it is neither a ferromagnet with mostly aligned magnetic particles, nor is it an antiferromagnet with mostly opposed adjacent magnetic particles; rather its magnetic particles have constantly fluctuating scattered orientations.
Optical conductivity observations[7] suggest the magnetic state in herbertsmithite is a type of emergent gauge field of a gapless U(1) Dirac spin liquid. Other experiments [8][9][10] and some calculations suggest instead that it is a spin liquid.[11]
References
[edit]- ^ Warr, L.N. (2021). "IMA–CNMNC approved mineral symbols". Mineralogical Magazine. 85 (3): 291–320. Bibcode:2021MinM...85..291W. doi:10.1180/mgm.2021.43. S2CID 235729616.
- ^ a b Herbertsmithite at mindat.org
- ^ "Information on Herbertsmithite on Webmineral". Webmineral.com. Retrieved 2013-03-06.
- ^ a b Braithwaite, RSW; Mereiter, K; Paar, WH; Clark, AM (1004). "Herbertsmithite, Cu3Zn(OH)6Cl2, a new species, and the definition of paratacamite" (PDF). Mineralogical Magazine. 68: 527–539. doi:10.1180/0026461046830204.
- ^ Shaginyan, V. R.; et al. (2012). "Identification of Strongly Correlated Spin Liquid in Herbertsmithite". EPL. 97 (5): 56001. arXiv:1111.0179. Bibcode:2012EL.....9756001S. doi:10.1209/0295-5075/97/56001. S2CID 119288349.
- ^ "MIT researchers discover a new kind of magnetism". Web.mit.edu. 2012-12-19. Retrieved 2013-03-06.
- ^ Pilon; et al. (2013). "Spin-Induced Optical Conductivity in the Spin-Liquid Candidate Herbertsmithite". Physical Review Letters. 111 (12): 127401. arXiv:1301.3501. Bibcode:2013PhRvL.111l7401P. doi:10.1103/PhysRevLett.111.127401. hdl:1721.1/84975. PMID 24093299. S2CID 5736968.
- ^ Han, Tian-Heng; Helton, Joel S.; Chu, Shaoyan; Nocera, Daniel G.; Rodriguez-Rivera, Jose A.; Broholm, Collin; Lee, Young S. (2012). "Fractionalized excitations in the spin-liquid state of a kagome-lattice antiferromagnet". Nature. 492 (7429): 406–410. arXiv:1307.5047. Bibcode:2012Natur.492..406H. doi:10.1038/nature11659. ISSN 0028-0836. PMID 23257883. S2CID 4344923.
- ^ Fu, M.; Imai, T.; Han, T.-H.; Lee, Y. S. (2015-11-05). "Evidence for a gapped spin-liquid ground state in a kagome Heisenberg antiferromagnet". Science. 350 (6261): 655–658. arXiv:1511.02174. Bibcode:2015Sci...350..655F. doi:10.1126/science.aab2120. ISSN 0036-8075. PMID 26542565. S2CID 22287797.
- ^ Han, Tian-Heng; Norman, M. R.; Wen, J.-J.; Rodriguez-Rivera, Jose A.; Helton, Joel S.; Broholm, Collin; Lee, Young S. (2016-08-18). "Correlated impurities and intrinsic spin-liquid physics in the kagome material herbertsmithite". Physical Review B. 94 (6): 060409. arXiv:1512.06807. Bibcode:2016PhRvB..94f0409H. doi:10.1103/physrevb.94.060409. ISSN 2469-9950.
- ^ Shaginyan, V. R.; et al. (2019). "Thermodynamic, Dynamic, and Transport Properties of Quantum Spin Liquid in Herbertsmithite from an Experimental and Theoretical Point of View". Condensed Matter. 4 (3): 75. arXiv:1908.10736. doi:10.3390/condmat4030075.