Non-Archimedes mosaic lattice structure and compound material thereof

Abstract

The invention belongs to the field of condensed physical and quantum materials, and discloses a non-Archimedes mosaic lattice structure and a compound material thereof. The lattice is a periodic network which is formed by closely arranging and splicing at least three different types of geometrical shapes (including triangles, quadrangles, pentagons and the like) in a two-dimensional plane in a common-edge or common-angle mode, and a traditional Archimedes lattice frame is broken through. The preparation of the single crystal from the compound A3M9X13 (such as Rb3V9Te13 and Cs3V9Te13) of the crystal lattice through a fluxing agent method is realized for the first time. Wherein Rb3V9Te13 belongs to an orthorhombic system and contains a distorted pentagonal unit; the Cs3V9Te13 belongs to a hexagonal crystal system, and the symmetry is higher. According to the structure, complex file blocking units such as pentagons are introduced, a unique platform is provided for exploring quantum singular matter states, and the compound has structure tunability.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of condensed matter physics and quantum materials, and relates to a non-Archimedean mosaic lattice structure and a compound material thereof. BACKGROUND

[0002] The exploration of novel physical properties is often inseparable from the discovery of new lattice geometrical structures. For example, Onsager's exact solution of the two-dimensional square lattice Ising model revealed the basic rules of phase transitions; the introduction of the cage lattice by Syozi et al. has become a classic platform for studying exotic quantum states and complex phase behaviors. Therefore, the discovery of a new type of lattice structure often brings important research opportunities and breakthroughs to the fields of condensed matter physics, quantum materials and related disciplines.

[0003] Currently, the most similar technical solutions to the present application in the field of geometric frustration and novel quantum states mainly focus on Archimedean lattices. Typical representatives of such lattices include cage lattices, maple leaf lattices, ruby lattices, lattice lattices, and star lattices, etc. These lattice structures provide an important theoretical basis and material platform for understanding the physical phenomena in geometrically frustrated systems.

[0004] However, the above-mentioned prior art has certain limitations. The core disadvantage is that the current research platform for geometric frustration and novel quantum states mainly focuses on compounds of Archimedean lattices. The relative solidification of this research path limits the complexity and diversity of lattice geometrical structures, which restricts the possibility of exploring novel quantum states in more complex geometric environments, thereby hindering the process of discovering new physical phenomena. Therefore, it is urgent to propose a new type of lattice structure that goes beyond the traditional framework of Archimedean lattices to open up new research directions. SUMMARY

[0005] The present application aims to overcome the shortcomings of the prior art and provide a non-Archimedean mosaic lattice structure and a compound material thereof to solve the problems raised in the technical background.

[0006] To achieve the above-mentioned purpose, the present application realizes the following technical solutions: In a first aspect, the present application provides a non-Archimedean mosaic lattice structure, which is a periodic network formed by at least three different types of geometric shapes in a two-dimensional plane through edge-sharing or corner-sharing manner; the geometric shapes include any three or more combinations of triangles, quadrilaterals, pentagons and hexagons.

[0007] Preferably, the mosaic lattice structure does not belong to the category of Archimedean lattices.

[0008] Preferred: pentagons are one of the lattice building blocks, where pentagons are the geometrically frustrated core unit.

[0009] Preferred: the geometric shapes include a combination of triangles, quadrilaterals and pentagons.

[0010] Preferred: the triangles, quadrilaterals and pentagons are all irregular shapes, satisfying the crystal symmetry by distortion.

[0011] In a second aspect, the present application provides a compound material with the mosaic lattice structure of the first aspect, the chemical formula of the compound is A3M9X 13 , wherein: A is an alkali metal element, M is a transition metal element, and X is a chalcogen element.

[0012] Preferred: A is selected from at least one of rubidium (Rb), cesium (Cs), and potassium (K); M is selected from at least one of vanadium (V), molybdenum (Mo), and tungsten (W); X is selected from at least one of tellurium (Te), selenium (Se), and sulfur (S).

[0013] Preferred: the compound is Rb3V9Te 13 or Cs3V9Te 13 .

[0014] Preferred: Rb3V9Te 13 belongs to the orthorhombic system, and the two-dimensional mosaic layer is stacked in the form of A-B-A-B along the c-axis with a layer spacing of 7.93 Å; Cs3V9Te 13 belongs to the hexagonal system, space group P-62m, and the two-dimensional layer is composed of one square, one pentagon, and two equilateral triangles.

[0015] In a third aspect, the present application provides a method for preparing the compound material of the second aspect, using a flux method to synthesize a millimeter-sized single crystal.

[0016] Preferred: the specific preparation method using the flux method is: A3M9X 13 The single crystal is grown by AX self-flux method. According to the ratio of A: M: X = 11: 9: 23, it is put into a specific alumina crucible (Canfield Crucible Sets, CCS) and sealed in a Ta tube. Then, the Ta tube is sealed in a vacuum quartz tube, and then heated to 900℃ within 10 hours, kept at this temperature for 12 hours to realize homogenization, and then uniformly cooled to 650℃ at a control rate of 1℃ / h. After cooling, the quartz tube is quickly transferred to a centrifuge to separate the excess flux. Finally, a millimeter-sized single crystal is obtained.

[0017] This invention provides novel and more complex frustrated geometries that hold promise for fostering new quantum states. While existing technologies such as Archimedean lattices (e.g., kagome lattices) are important material platforms, their geometries are relatively simple.

[0018] The "mosaic lattice" discovered in this invention creates a more complex geometrically frustrated environment than traditional Archimedean lattices by introducing a mixed tiling of various geometric shapes (such as triangles, squares, and pentagons). This unique geometric structure fundamentally changes the competitive relationship of spin interactions in the system, thus potentially generating novel quantum phenomena and states of matter different from known Archimedean systems, opening up entirely new research directions for exploring novel quantum states. Compared with the prior art, the beneficial effects of the present invention are: 1. The crystal structure of this invention surpasses the traditional Archimedean lattices such as triangular and Kagome, and introduces more complex geometrically frustrated units, fundamentally providing a unique physical carrier for the generation of new quantum phenomena (such as quantum spin liquid state).

[0019] 2. Provides the first physical form of a periodic lattice material containing pentagons, filling the structural gap outside of the Archimedes lattice; 3. The compounds can be synthesized in single crystals, exhibiting high structural flexibility and tunability. Tunability: By controlling the A-site elements (e.g., Rb→Cs), the lattice symmetry (orthorhombic to hexagonal) and geometric distortion can be adjusted. Attached Figure Description

[0020] Figure 1 Rb3V3Te 13 Crystal structure of (RVT); wherein, (a) three-dimensional framework structure of RVT; (b) two-dimensional mosaic lattice based on V atoms; (c) coordination environment of Rb atoms and V atoms respectively; (d) stacking form of V-based layers; (e) constituent units of triangles, squares and pentagons in two-dimensional mosaic lattice.

[0021] Figure 2 For Cs3V9Te 13 Crystal structure of CVT; (a) Three-dimensional framework structure of CVT; (b) Two-dimensional mosaic lattice based on V atoms; (c) Coordination environment of Cs and V atoms; (d) Stacking of V-based layers; (e) Triangular, square and pentagonal constituent units in the two-dimensional mosaic lattice. Detailed Implementation

[0022] Following embodiments of the present application are illustrated by way of specific examples, and other advantages and effects of the present application can be easily understood by those skilled in the art from the disclosure. The present application can also be implemented or applied by way of other different embodiments, and various modifications or changes can be made to the details based on different views and applications without departing from the spirit of the present application. It should be noted that the following examples and features in the examples can be combined with each other without conflict.

[0023] The present application provides a non-Archimedean mosaic lattice structure, which is a periodic network formed by at least three different types of geometric shapes in a two-dimensional plane by edge-sharing or corner-sharing.

[0024] As an embodiment of the present application, the present application proposes a brand new mosaic lattice structure, which is formed by triangular, quadrilateral and pentagonal shapes. Based on this, we successfully synthesized compound A3V9Te13(A=Rb, Cs) with such a mosaic lattice, and taking this compound as a representative example, we show the specific geometric configuration and structural characteristics of the mosaic lattice.

[0025] Example 1: Rb3V9Te 13 Single crystal preparation and structure characterization 1. Preparation method: Flux method is used to mix Rb, V and Te raw materials according to the stoichiometric ratio, melt at high temperature and slowly cool to obtain millimeter-sized single crystals. A3M9X 13 Single crystals (A=Rb, M=V, X=Te) are grown by AX self-flux method. A: M: X = 11: 9: 23 is placed in a specific alumina crucible (Canfield Crucible Sets, CCS) and sealed in a Ta tube. Then, the Ta tube is sealed in a vacuum quartz tube, and then heated to 900°C within 10 hours, kept at this temperature for 12 hours to achieve homogenization, and then cooled to 650°C at a controlled rate of 1°C / h. After cooling, the quartz tube is quickly transferred to a centrifuge to separate excess flux. Finally, millimeter-sized single crystals are obtained.

[0026] 2. Rb3V9Te 13 Mosaic lattice structure analysis: As Figure 1 shown, in the asymmetric unit of Rb3V9Te 13 , there are five independent Te positions, two Rb positions (4a, 8e) and five V positions Figure 1a) The two-dimensional mosaic layers adopt A-B-A-B stacking along the crystallographic c-axis with an interlayer spacing of 7.93 Å Figure 1 b, Figure 1 d) In the ab plane, V atoms form a two-dimensional mosaic arrangement, with each V connected to four nearest neighbors. Geometrically, the two-dimensional mosaic layers in Rb3V9Te 13 can be described as a network composed of two types of triangles, two types of squares, and two types of pentagons Figure 1 e) Each V-based triangle is connected to three squares and three pentagons by sharing edges and corners, respectively. Notably, five-fold rotational symmetry is crystallographically forbidden. To satisfy the crystal symmetry, the lattice adopts a mixed tiling of triangles, squares, and pentagons, each of which experiences slight distortion and is no longer regular. The V-V bond distances of the five edges of the pentagon range from 3.06 to 3.17 Å. The V-based triangles are also distorted, lacking 3-fold or 6-fold rotational symmetry, which is consistent with the orthorhombic symmetry of Rb3V9Te 13 . Example 2: Cs3V9Te 13 Single crystal preparation and structure characterization 1. Preparation method: same as Example 1, raw materials are replaced by Cs, V, and Te.

[0027] 2. Cs3V9Te 13 Mosaic lattice structure analysis: Compared with Rb3V9Te 13 , Cs3V9Te 13 exhibits higher symmetry and crystallizes in the hexagonal system with space group P-62m. In the asymmetric unit of Cs3V9Te 13 , there are three independent Te positions (4h, 6i, 3g), one Cs position (3f), and two V positions (3g, 6k). The two-dimensional layers in Cs3V9Te 13 are composed of one square, one pentagon, and two triangles Figure 2 . Due to the higher crystal symmetry, both of the two triangular units are equilateral, despite having different V-V bond lengths. As expected, the crystal symmetry is adjusted from the low-symmetry Rb-based compounds to the high-symmetry Cs-based compounds, highlighting the tunability and structural flexibility of the mosaic lattice Figure 2 . The above-described examples only express specific embodiments of the present application, which are described in more detail and in more detail, but cannot be construed as limiting the scope of protection of the present application. It should be noted that for those skilled in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are within the scope of protection of the present application.

Claims

1. A non-Archimedean mosaic lattice structure, characterized in that, A periodic network consisting of at least three different types of geometric shapes closely arranged in a two-dimensional plane by sharing sides or angles; the geometric shapes include any three or more combinations of triangles, quadrilaterals, pentagons and hexagons.

2. The mosaic lattice structure according to claim 1, characterized in that, The mosaic lattice structure does not belong to the category of Archimedes lattices.

3. The mosaic lattice structure according to claim 2, characterized in that, The geometric shapes include combinations of triangles, quadrilaterals, and pentagons.

4. The mosaic lattice structure according to claim 3, characterized in that, The triangles, quadrilaterals, and pentagons are all irregular shapes, and the distortion satisfies the crystal symmetry.

5. A compound material having the mosaic lattice described in any one of claims 1-4, characterized in that: The chemical formula of the compound is A3M9X. 13 Where: A is an alkali metal element, M is a transition metal element, and X is a chalcogen group element.

6. The compound material according to claim 5, characterized in that: A is selected from at least one of rubidium, cesium, potassium (Rb), Cs, and K; M is selected from at least one of vanadium, molybdenum, and tungsten; X is selected from at least one of tellurium, selenium, and sulfur.

7. The compound material according to claim 6, characterized in that: The compound is Rb3V9Te 13 or Cs3V9Te 13 .

8. The compound material according to claim 7, characterized in that: Rb3V9Te 13 It belongs to the orthorhombic crystal system, and the two-dimensional mosaic layers are stacked along the c-axis in an ABAB pattern with an interlayer spacing of 7.93 Å; Cs3V9Te 13 It belongs to the hexagonal crystal system, space group P-62m, and its two-dimensional layers consist of a square, a pentagon and two equilateral triangles.

9. A method for preparing the compound material according to any one of claims 4-7, characterized in that: Millimeter-scale single crystals were synthesized using a flux method.

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