# US 2020/0392011 A1 · Polar Oxysulfide for Nonlinear Optical Applications

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 2020/0392011 A1
- Document ID: US20200392011A1
- Status: Published application
- Kind: A1
- Application number: 16/918,155
- Filed: 2020-07-01
- Published: 2020-12-17
- Earliest claimed: 2018-09-05
- Assignees: University of South Carolina; National Institute for Materials Science
- Applicants: University of South Carolina; National Institute For Materials Science
- Inventors: Hans-Conrad Zur Loye; Yoshihiro Tsujimoto
- Web page: https://patentgrep.com/patent/US20200392011A1

## CPC

- C01G 9/006: {Compounds containing zinc, with or without oxygen or hydrogen, and containing two or more other elements}
- B01J 2/22: by pressing in moulds or between rollers
- C01P 2002/20: Two-dimensional structures
- C01P 2002/72: by d-values or two theta-values, e.g. as X-ray diagram
- C01P 2002/76: by a space-group or by other symmetry indications
- C01P 2002/77: by unit-cell parameters, atom positions or structure diagrams
- C01P 2002/78: by stacking-plane distances or stacking sequences
- C01P 2002/84: by UV- or VIS- data
- C01P 2002/88: by thermal analysis data, e.g. TGA, DTA, DSC
- C01P 2004/51: Particles with a specific particle size distribution
- C01P 2004/61: Micrometer sized, i.e. from 1-100 micrometer
- C01P 2006/37: Stability against thermal decomposition
- C01P 2006/40: Electric properties
- G02F 1/3551: {Crystals}
- G02F 1/37: for second-harmonic generation {(G02F1/3532 takes precedence)}
- C01G: COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F (metal hydrides {monoborane, diborane or addition complexes thereof} C01B6/00; salts of oxyacids of halogens C01B11/00; peroxides, salts or peroxyacids C01B15/00; thiosulfates, dithionites, polythionates C01B17/64; compounds containing selenium, or tellurium C01B19/00; binary compounds of nitrogen with metals C01B21/06; azides C01B21/08; {compounds containing nitrogen, other non-metals and metal C01B21/082}; metal amides C01B21/092; nitrites C01B21/50; {compounds of noble gases C01B23/0005}; phosphides C01B25/08; salts of oxyacids of phosphorus C01B25/16; carbides C01B32/90; compounds containing silicon C01B33/00; compounds containing boron C01B35/00; compounds having molecular sieve properties but not having base-exchange properties C01B37/00; compounds having molecular sieve and base-exchange properties, e.g. crystalline zeolites, C01B39/00; cyanides C01C3/08; salts of cyanamide C01C3/16; thiocyanates C01C3/20)
- B01J: CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- C01P: INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- G02F: OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS

## Abstract

Single crystals of a new noncentrosymmetric polar oxysulfide SrZn2S2O (s.g. Pmn21) grown in a eutectic KF-KCl flux with unusual wurtzite-like slabs consisting of close-packed corrugated double layers of ZnS3O tetrahedra vertically separated from each other by Sr atoms and methods of making same.

## Claims

### Claim 1

A new zinc oxysulfide compound comprising;
a noncentrosymmetric crystalline structure with chemical formula SrZn2S2O;
lattice parameters of α=3.87440(10) Å, b=9.9847(3) Å, and c=6.0916(2) Å; and
corrugated double layers of ZnS3O tetrahedra vertically separated by Sr2+ ions.

### Claim 2 (depends on 1)

The new zinc oxysulfide compound of claim 1, wherein an O/S anion ordered arrangement provides two distinct orientations of the ZnS3O tetrahedra.

### Claim 3 (depends on 1)

The new zinc oxysulfide compound of claim 1, wherein the compound crystalizes in noncentrosymmetric polar space group Pmn21.

### Claim 4 (depends on 1)

The new zinc oxysulfide compound of claim 1, wherein an O/S anion ordered arrangement yields two distinct orientations of the Zn-centered tetrahedra.

### Claim 5 (depends on 1)

The new zinc oxysulfide compound of claim 1, wherein the compound forms colorless, transparent crystals.

### Claim 6 (depends on 1)

The new zinc oxysulfide compound of claim 1, having a band gap of 3.86 eV.

### Claim 7 (depends on 1)

The new zinc oxysulfide compound of claim 1, wherein the compound is stable up to 650° C. in O2 gas atmosphere.

### Claim 8 (depends on 1)

The new zinc oxysulfide compound of claim 1, wherein the compound is phase matchable with twice a SHG intensity of potassium dihydrogen phosphate (KDP).

### Claim 9 (depends on 1)

The new zinc oxysulfide compound of claim 1, wherein the compound has a Sr:Zn:S molar ratio of approximately 1.0:2.0:2.3.

### Claim 10 (depends on 1)

The new zinc oxysulfide compound of claim 1, wherein the compound has a band gap energy of 3.86 eV.

### Claim 11 (depends on 1)

The new zinc oxysulfide compound of claim 1, wherein temperatures greater than 1000° C. decompose the SrZn2S2O compound

### Claim 12

A method for synthesizing the compound SrZn2S2O comprising:
employing a molten salt method using a eutectic KF-KCl mixture;
loading a silver tube with 1 mmol of SrO, 1 mmol of Zn, 1 mmol of S, 3.4 mmol of KF, and 4.1 mmol of KCl;
placing the silver tube in a silica tube that was evacuated to 10−4 Pa and sealed; and
heating the silver tube in a tube furnace to 900° C. at 5° C./min, held for 24 h, and cooled to 600° C. at 0.17° C./min.

### Claim 13 (depends on 12)

The method of claim 12, further comprising, extracting the compound from flux by dissolving the flux in water followed by sonication.

### Claim 14

A method for solid state synthesis of SrZn2S2O comprising:
mixing SRO, Zn and S in a stoichiometric ratio in an agate mortar to form a mixture;
pressing the mixture into a pellet;
heating the pellet in an evacuated silica tube at 1000° C. for 24 hours; and
sonicating at 1000° C. with water.