The kagome lattice, composed of a planar array of corner-sharing triangles, is one of the most geometrically frustrated lattices. The realization of a spin S = 1/2 kagome lattice antiferromagnet is of particular interest because it may host an exotic form of matter, a quantum spin liquid state, which shows long-range entanglement and no magnetic ordering down to 0 K. A few S = 1/2 kagome lattice antiferromagnets exist, typically based on Cu2+, d9 compounds, though they feature structural imperfections. Herein, we present the synthesis of (CH3NH3)2NaTi3F12, which comprises an S = 1/2 kagome layer that exhibits only one crystallographically distinct Ti3+, d1 site, and one type of bridging fluoride. A static positional disorder is proposed for the interlayer CH3NH3+. No structural phase transitions were observed from 1.8 K to 523 K. Despite its spin-freezing behaviour, other features—including its negative Curie–Weiss temperature and a lack of long-range ordering—imply that this compound is a highly frustrated magnet with unusual magnetic phase behaviours.
Subscribe to Journal
Get full journal access for 1 year
only $4.92 per issue
All prices are NET prices.
VAT will be added later in the checkout.
Tax calculation will be finalised during checkout.
Rent or Buy article
Get time limited or full article access on ReadCube.
All prices are NET prices.
Crystallographic data for the structures reported in this Article have been deposited at the Cambridge Crystallographic Data Centre, under deposition numbers CCDC 1950701 (1-Ti, 100 K) and 1950702 (1-Ti, 298 K). Copies of the data can be obtained free of charge via https://www.ccdc.cam.ac.uk/structures/. All data generated or analysed during this study are included in this published article and its Supplementary Information files.
Ramirez, A. Strongly geometrically frustrated magnets. Annu. Rev. Mater. Sci. 24, 453–480 (1994).
Atwood, J. L. Kagome lattice: a molecular toolkit for magnetism. Nat. Mater. 1, 91–92 (2002).
Grohol, D., Nocera, D. G. & Papoutsakis, D. Magnetism of pure iron jarosites. Phys. Rev. B Condens. Matter 67, 064401 (2003).
Freedman, D. E. et al. Frustrated magnetism in the S = 1 kagome lattice BaNi3(OH)2(VO4)2. Chem. Commun. 48, 64–66 (2012).
Paul, G., Choudhury, A., Sampathkumaran, E. V. & Rao, C. N. R. Organically templated mixed‐valent iron sulfates possessing kagomé and other types of layered networks. Angew. Chem. Int. Ed. 41, 4297–4300 (2002).
Grohol, D. et al. Spin chirality on a two-dimensional frustrated lattice. Nat. Mater. 4, 323–328 (2005).
Hara, S., Sato, H. & Narumi, Y. Exotic magnetism of novel S = 1 kagome lattice antiferromagnet KV3Ge2O9. J. Phys. Soc. Jpn. 81, 073707 (2012).
Balents, L. Spin liquids in frustrated magnets. Nature 464, 199–208 (2010).
Yan, S., Huse, D. A. & White, S. R. Spin-liquid ground state of the S = 1/2 kagome Heisenberg antiferromagnet. Science 332, 1173–1176 (2011).
Broholm, C. et al. Quantum spin liquids. Science 367, eaay0668 (2020).
Itou, T., Oyamada, A., Maegawa, S., Tamura, M. & Kato, R. Spin-liquid state in an organic spin-1/2 system on a triangular lattice, EtMe3Sb[Pd(dmit)2]2. J. Phys. Condens. Matter 19, 145247 (2007).
Okamoto, Y., Nohara, M., Aruga-Katori, H. & Takagi, H. Spin-liquid state in the S = 1/2 hyperkagome antiferromagnet Na4Ir3O8. Phys. Rev. Lett. 99, 137207 (2007).
Yamashita, S. et al. Thermodynamic properties of a spin-1/2 spin-liquid state in a κ-type organic salt. Nat. Phys. 4, 459–462 (2008).
Okamoto, Y., Yoshida, H. & Hiroi, Z. Vesignieite BaCu3V2O8(OH)2 as a candidate spin-1/2 kagome antiferromagnet. J. Phys. Soc. Jpn. 78, 033701–033701 (2009).
Pasco, C. et al. Single-crystal growth of Cu4(OH)6BrF and universal behavior in quantum spin liquid candidates synthetic barlowite and herbertsmithite. Phys. Rev. Mater. 2, 044406 (2018).
Han, T.-H. et al. Fractionalized excitations in the spin-liquid state of a kagome-lattice antiferromagnet. Nature 492, 406–410 (2012).
Shores, M. P., Nytko, E. A., Bartlett, B. M. & Nocera, D. G. A structurally perfect S = 1/2 kagome antiferromagnet. J. Am. Chem. Soc. 127, 13462–13463 (2005).
Fu, M., Imai, T., Han, T.-H. & Lee, Y. S. Evidence for a gapped spin-liquid ground state in a kagome Heisenberg antiferromagnet. Science 350, 655–658 (2015).
Freedman, D. E. et al. Site specific X-ray anomalous dispersion of the geometrically frustrated kagomé magnet, herbertsmithite, ZnCu3(OH)6Cl2. J. Am. Chem. Soc. 132, 16185–16190 (2010).
Mendels, P. & Bert, F. Quantum kagome antiferromagnet ZnCu3(OH)6Cl2. J. Phys. Soc. Jpn. 79, 011001 (2010).
Aidoudi, F. H. et al. An ionothermally prepared S = 1/2 vanadium oxyfluoride kagome lattice. Nat. Chem. 3, 801–806 (2011).
Clark, L. et al. Gapless spin liquid ground state in the S = 1/2 vanadium oxyfluoride kagome antiferromagnet [NH4]2[C7H14N][V7O6F18]. Phys. Rev. Lett. 110, 207208 (2013).
Nocera, D. G., Bartlett, B. M., Grohol, D., Papoutsakis, D. & Shores, M. P. Spin frustration in 2D kagome lattices: a problem for inorganic synthetic chemistry. Chem. Eur. J. 10, 3850–3859 (2004).
Bendix, J., Brorson, M. & Schaffer, C. E. Accurate empirical spin-orbit coupling parameters ζnd for gaseous ndq transition metal ions. The parametrical multiplet term model. Inorg. Chem. 32, 2838–2849 (1993).
Jeschke, H. O., Nakano, H. & Sakai, T. From kagome strip to kagome lattice: realizations of frustrated S = 1/2 antiferromagnets in Ti(iii) fluorides. Phys. Rev. B Condens. Matter 99, 140410 (2019).
Nilsen, G. et al. One-dimensional quantum magnetism in the anhydrous alum KTi(SO4)2. New J. Phys. 17, 113035 (2015).
Sabatier, R. et al. Structural and magnetic studies of cesium fluorotitanate (CsTiF4). Mater. Res. Bull. 17, 369–377 (1982).
Dadachov, M. & Eriksson, L. Diammonium titanium pentafluoride, (NH4)2TiF5, containing Ti3+. Acta Crystallogr. C 55, 1739–1741 (1999).
Jo, V., Lee, D. W., Koo, H.-J. & Ok, K. M. A2TiF5·nH2O (A = K, Rb, or Cs; n = 0 or 1): synthesis, structure, characterization, and calculations of three new uni-dimensional titanium fluorides. J. Solid State Chem. 184, 741–746 (2011).
Goto, M. et al. Various disordered ground states and 1/3 magnetization-plateau-like behavior in the S = 1/2 Ti3+ kagome lattice antiferromagnets Rb2NaTi3F12, Cs2NaTi3F12, and Cs2KTi3F12. Phys. Rev. B Condens. Matter 94, 104432 (2016).
Armstrong, J. A., Williams, E. R. & Weller, M. T. Fluoride-rich, hydrofluorothermal routes to functional transition metal (Mn, Fe, Co, Cu) fluorophosphates. J. Am. Chem. Soc. 133, 8252–8263 (2011).
Brese, N. & O’Keeffe, M. Bond-valence parameters for solids. Acta Crystallogr. B 47, 192–197 (1991).
Brown, I. A determination of the oxidation states and internal stresses in Ba2YCu3Ox, x = 6–7 using bond valences. J. Solid State Chem. 82, 122–131 (1989).
Reinen, D., Atanasov, M., Köhler, P. & Babel, D. Jahn–Teller coupling and the influence of strain in Tg and Eg ground and excited states—a ligand field and DFT study on halide MIIIX6 model complexes [M = TiIII–CuIII; X = F−, Cl−]. Coord. Chem. Rev. 254, 2703–2754 (2010).
Rao, C. N. R. et al. Synthesis, structure, and the unusual magnetic properties of an amine-templated iron (ii) sulfate possessing the kagome lattice. Chem. Mater. 16, 1441–1446 (2004).
Reisinger, S. A., Tang, C. C., Thompson, S. P., Morrison, F. D. & Lightfoot, P. Structural phase transition in the S = 1/2 kagome system Cs2ZrCu3F12 and a comparison to the valence-bond-solid phase in Rb2SnCu3F12. Chem. Mater. 23, 4234–4240 (2011).
Ono, T. et al. Magnetic susceptibilities in a family of S = 1/2 kagome antiferromagnets. Phys. Rev. B Condens. Matter 79, 174407 (2009).
Kelly, Z. A., Tran, T. T. & McQueen, T. M. Nonpolar-to-polar trimerization transitions in the S = 1 kagome magnet Na2Ti3Cl8. Inorg. Chem. 58, 11941–11948 (2019).
Besara, T. et al. Mechanism of the order–disorder phase transition, and glassy behavior in the metal–organic framework [(CH3)2NH2]Zn(HCOO)3. Proc. Natl Acad. Sci. USA 108, 6828–6832 (2011).
Fabini, D. H. et al. Dielectric and thermodynamic signatures of low-temperature glassy dynamics in the hybrid perovskites CH3NH3PbI3 and HC(NH2)2PbI3. J. Phys. Chem. Lett. 7, 376–381 (2016).
Fabini, D. H. et al. Universal dynamics of molecular reorientation in hybrid lead iodide perovskites. J. Am. Chem. Soc. 139, 16875–16884 (2017).
Scheie, A. LongHCPulse: long-pulse heat capacity on a quantum design PPMS. J. Low Temp. Phys. 193, 60–73 (2018).
Bert, F. et al. Low temperature magnetization of the S = 1/2 kagome antiferromagnet ZnCu3(OH)6Cl2. Phys. Rev. B Condens. Matter 76, 132411 (2007).
Sinha, M. et al. Introduction of spin centers in single crystals of Ba2CaWO6−δ. Phys. Rev. Mater. 3, 125002 (2019).
Helton, J. et al. Spin dynamics of the spin-1/2 kagome lattice antiferromagnet ZnCu3(OH)6Cl2. Phys. Rev. Lett. 98, 107204 (2007).
Mydosh, J. A. Spin Glasses: an Experimental Introduction (CRC Press, 2014).
Ma, Z. et al. Spin-glass ground state in a triangular-lattice compound YbZnGaO4. Phys. Rev. Lett. 120, 087201 (2018).
Balz, C. et al. Physical realization of a quantum spin liquid based on a complex frustration mechanism. Nat. Phys. 12, 942–949 (2016).
Liu, W. et al. Rare-earth chalcogenides: a large family of triangular lattice spin liquid candidates. Chin. Phys. Lett. 35, 117501 (2018).
Li, Y. et al. Rearrangement of uncorrelated valence bonds evidenced by low-energy spin excitations in YbMgGaO4. Phys. Rev. Lett. 122, 137201 (2019).
Bordelon, M. M. et al. Field-tunable quantum disordered ground state in the triangular-lattice antiferromagnet NaYbO2. Nat. Phys. 15, 1058–1064 (2019).
Kimchi, I., Nahum, A. & Senthil, T. Valence bonds in random quantum magnets: theory and application to YbMgGaO4. Phys. Rev. X 8, 031028 (2018).
Feng, Z. et al. Gapped spin-1/2 spinon excitations in a new kagome quantum spin liquid compound Cu3Zn(OH)6FBr. Chin. Phys. Lett. 34, 077502 (2017).
Bertolini, J. C. Hydrofluoric acid: a review of toxicity. J. Emerg. Med. 10, 163–168 (1992).
Peters, D. & Miethchen, R. Symptoms and treatment of hydrogen fluoride injuries. J. Fluor. Chem. 79, 161–165 (1996).
CrysAlisPro Software system v.220.127.116.11a (Rigaku Corporation, 2015).
Sheldrick, G. M. Crystal structure refinement with SHELXL. Acta Crystallogr. C 71, 3–8 (2015).
Sheldrick, G. M. SHELXT–integrated space-group and crystal-structure determination. Acta Crystallorgr. A Found. Adv. 71, 3–8 (2015).
Dolomanov, O. V., Bourhis, L. J., Gildea, R. J., Howard, J. A. & Puschmann, H. OLEX2: a complete structure solution, refinement and analysis program. J. Appl. Crystallogr. 42, 339–341 (2009).
Schnelle, W., Engelhardt, J. & Gmelin, E. Specific heat capacity of Apiezon N high vacuum grease and of Duran borosilicate glass. Cryogenics 39, 271–275 (1999).
Studies were supported by the Beckman Foundation as part of a Beckman Young Investigator Award to H.S.L. Single-crystal diffraction experiments were performed at the Georgia Institute of Technology SCXRD facility, established with funding from the Georgia Institute of Technology. We thank M. Mourigal for providing access to a PPMS. This work was performed in part at the Georgia Tech Institute for Electronics and Nanotechnology, a member of the National Nanotechnology Coordinated Infrastructure (NNCI), which is supported by the National Science Foundation (grant ECCS-1542174). The low-temperature PXRD experiment was conducted at the Center for Nanophase Materials Sciences, which is a US Department of Energy (DOE) Office of Science User Facility. A portion of this research used resources at the Spallation Neutron Source, a DOE Office of Science User Facility operated by the Oak Ridge National Laboratory. We thank Q. Zhang and J. K. Keum for their help with neutron powder diffraction and low-temperature PXRD studies, respectively.
The authors declare no competing interests.
Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
About this article
Cite this article
Jiang, N., Ramanathan, A., Bacsa, J. et al. Synthesis of a d1-titanium fluoride kagome lattice antiferromagnet. Nat. Chem. 12, 691–696 (2020). https://doi.org/10.1038/s41557-020-0490-8
Nachrichten aus der Chemie (2020)
Chemical Science (2020)
Realizing square and diamond lattice S=1/2 Heisenberg antiferromagnet models in the α and β phases of the coordination framework, KTi(C2O4)2·xH2O
Physical Review Materials (2020)
Physical Chemistry Chemical Physics (2020)
Chemical Communications (2020)