Amino methanesulfonic acid second-order nonlinear optical crystal as well as preparation and application thereof

Abstract

The invention relates to a second-order nonlinear optical material crystal amino methanesulfonic acid as well as preparation and application thereof. The chemical formula of the crystal is O3SCH2NH3, the molecular weight of the crystal is 111.12, the crystal belongs to a monoclinic system, the space group of the crystal is Cm, the cell parameters are alpha = gamma = 90 degrees, beta = 129.7-131.7 degrees, Z = 2, and the cell volume of the crystal is structurally characterized in that the crystalline material is a three-dimensional frame formed by connecting [O3SCH2NH3] elements through hydrogen-bond interaction. The amino methanesulfonic acid crystal material has excellent optical performance, and under 1064nm laser irradiation, the powder frequency doubling intensity is about 3.8 times that of a KH2PO4 (KDP) crystal; under the irradiation of 532 nm laser, the frequency doubling strength of the powder is about 0.7 time of that of the beta-BaB2O4 (BBO) crystal, and phase matching can be realized. Besides, the crystal material has moderate birefringence at 546 nm, the ultraviolet absorption cut-off edge is smaller than 170 nm, and the crystal material has stable physical and chemical properties and has important application value in the photoelectric fields of photoetching, laser frequency conversion, environmental monitoring and the like.

Description

Technical Field

[0001] This invention belongs to the field of nonlinear optical crystal materials technology, and relates to a second-order nonlinear optical crystal material and its preparation and application.

[0002] Materials Research Background

[0003] Second-order nonlinear optical crystals are important optoelectronic functional materials, characterized by their frequency doubling effect (SHG), and have broad application prospects in ultrafine spectral analysis, semiconductor lithography, precision microfabrication, and photochemistry. Based on their transmission wavelength and applicable range, inorganic nonlinear optical crystal materials can be classified into ultraviolet, visible, and infrared regions. Currently commercially available ultraviolet nonlinear optical materials include barium β-borate (BBO), cesium borate (CsB3O5), and lithium borate (LBO). However, existing commercially available ultraviolet nonlinear optical materials still cannot fully meet practical needs. For example, BBO suffers from a walk-off effect due to its high birefringence, leading to a decrease in frequency doubling efficiency; CBO is prone to deliquescence. Therefore, developing ultraviolet frequency doubling crystals with superior performance has become an important research direction in the field of optoelectronic materials. Summary of the Invention

[0004] The present invention aims to provide a deep ultraviolet-transmitting second-order nonlinear optical crystal material of sulphic acid, its preparation method, and its applications. The oriented [SO3CH2NH3] units in the crystal structure significantly enhance the linear and nonlinear optical properties of the material. This crystal exhibits a strong powder overtone response (3.8 × KDP @ 1064 nm; 0.7 × BBO @ 532 nm), a moderate birefringence (0.06 @ 546 nm), and a short ultraviolet absorption cutoff edge (< 170 nm).

[0005] The objective of this invention can be achieved through the following technical solutions:

[0006] One technical solution of this invention provides a second-order nonlinear optical crystal material for deep ultraviolet transmission of methanesulfonic acid, characterized in that the chemical formula of the crystal material is O3SCH2NH3, the molecular weight is 111.12, it belongs to the monoclinic crystal system, its space group is Cm, and its cell parameters are... α=γ=90°, β=129.1°~131.7°, Z=2, cell volume is

[0007] Furthermore, the chemical formula of this crystalline material is O3SCH2NH3, its molecular weight is 111.12, it belongs to the monoclinic crystal system, its space group is Cm, and its unit cell parameters are... α = γ = 90°, β = 129.1°~131.7°, Z = 2. More preferably, the cell parameters are... α = γ = 90°, β = 130.2°~131.2°, Z = 2. Most preferably, the cell parameters are... α=γ=90°, β=130.7°, Z=2.

[0008] The crystal structure of the carbamate of the present invention is as follows: Figure 1 As shown, the structure presents as a three-dimensional hydrogen-bonded organic framework composed of [O3SCH2NH3] motifs linked by hydrogen bonds. Each [O3SCH2NH3] motif is connected to twelve neighboring motifs via NH…O and CH…O hydrogen bonds, ultimately extending to form [O3SCH2NH3]. ∞ Three-dimensional network. [SO4] primitive (T d When the O atoms in the symmetrical [O3SCH2NH3] motif are replaced by [CH2NH3] groups, the local symmetry decreases, the geometric configuration of the motif changes, and the formation of asymmetric local environments is promoted. The electrostatic interaction between acidic and basic components between adjacent motifs further promotes the orderly arrangement of [O3SCH2NH3] motifs along a specific direction.

[0009] The second objective of this invention is to propose a method for preparing a second-order nonlinear optical crystal material that transmits deep ultraviolet light using methanesulfonic acid, comprising the following steps:

[0010] (1) Take sulfonic acid source, mineralizing agent and water and mix them to form initial mixed raw materials;

[0011] (2) The initial mixed raw materials in step (1) are then slowly volatilized and crystallized at room temperature to obtain the target product.

[0012] Furthermore, in step (1), the sulfonic acid source is aminomethanesulfonic acid.

[0013] Furthermore, in step (1), the mineralizing agent is selected from at least one of lithium chloride, lithium hydroxide, lithium carbonate, lithium nitrate, and lithium acetate, and even more specifically, the mineralizing agent is lithium chloride.

[0014] Furthermore, in step (1), the amount of sulfonic acid source and mineralizer added satisfies the following: the molar ratio of S element to Li element is (10-30):(5-15), more preferably (16-24):(8-12).

[0015] Furthermore, in step (2), the temperature at which the solution evaporates is 25–55°C, more preferably 35–45°C. The evaporation time is not less than three days, more preferably not less than two weeks.

[0016] The third technical solution of the present invention provides an application of a sulfamic acid deep ultraviolet-transmitting second-order nonlinear optical crystal material in laser frequency converters, optical parametric oscillators, optical parametric amplifiers, and photoelectric rectifiers.

[0017] Furthermore, this material is used in laser frequency converters to output 532nm laser light under 1064nm laser irradiation.

[0018] Furthermore, this material is used in laser frequency converters to output 266nm laser light under 532nm laser irradiation.

[0019] Specifically, O3SCH2NH3 crystal, as a second-order nonlinear optical crystalline material, outputs a strong 532nm laser under 1064nm laser irradiation, and its powder frequency doubling intensity is 3.8 times that of KDP crystal. Under 532nm laser irradiation, it can output a 266nm laser, and its powder frequency doubling intensity is 0.7 times that of BBO crystal, both of which can achieve phase matching.

[0020] Compared with the prior art, the present invention has the following advantages:

[0021] (1) This application provides a novel nonlinear optical crystal, SO3CH2NH3, which exhibits a large frequency doubling effect. Under 1064 nm laser irradiation, its powder frequency doubling intensity is 3.8 times that of KDP crystal. Under 532 nm laser irradiation, it outputs a strong 266 nm laser, with a powder frequency doubling intensity 0.7 times that of BBO crystal, and it can achieve phase matching. Furthermore, this crystalline material has a short ultraviolet absorption cutoff edge (<70 nm) and a moderate birefringence (0.060@546 nm). This crystalline material has broad application prospects in the field of nonlinear optics.

[0022] (2) This application also provides a method for preparing the nonlinear optical crystal SO3CH2NH3, which uses a solution evaporation method to grow colorless SO3CH2NH3 crystals. The method is simple, the conditions are mild, and it is easy to grow single crystals with high optical quality and high purity.

[0023] (3) The carbamate crystal material of the present invention can be applied to a laser frequency converter and can be used to output a laser beam as a second harmonic. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the crystal structure of SO3CH2NH3;

[0025] Figure 2 It is a photograph of SO3CH2NH3 crystals;

[0026] Figure 3The X-ray diffraction pattern of sample 1# obtained by fitting the crystal structure resolved by single-crystal X-ray diffraction is compared with the X-ray diffraction pattern obtained by grinding sample 1# into powder.

[0027] Figure 4 This is the UV-Vis transmission spectrum of sample 1#;

[0028] Figure 5 This is the deep ultraviolet transmission spectrum of sample 1#;

[0029] Figure 6 This is the infrared spectrum of sample 1#;

[0030] Figure 7 This is the thermogravimetric analysis chromatogram of sample 1#;

[0031] Figure 8 This is the second harmonic phase matching diagram of sample 1# in the 1064nm band;

[0032] Figure 9 The diagram shows the second harmonic signal of sample 1# and KDP sample with dimensions in the range of 200-280μm.

[0033] Figure 10 This is the second harmonic phase matching diagram of sample 1# in the 532nm band;

[0034] Figure 11 The diagram shows the second harmonic signal of sample 1# and BBO sample with dimensions in the range of 200-280 μm.

[0035] Figure 12 This is a birefringence test result of sample 1# at a wavelength of 546nm. Detailed Implementation

[0036] The embodiments of the present invention are described in detail below. These embodiments are implemented based on the technical solution of the present invention, and provide detailed implementation methods and specific operation processes. However, the scope of protection of the present invention is not limited to the following embodiments.

[0037] In the following embodiments, unless otherwise specified, the raw materials or processing techniques are conventional commercially available raw materials or conventional processing techniques in the art.

[0038] Example 1:

[0039] Preparation of samples 1# to 8#

[0040] A sulfonic acid source, mineralizing agent, and water are mixed in a specific ratio to form a raw material. This mixture is placed in a glass beaker and stirred continuously until a clear, transparent solution is obtained. Colorless, transparent SO3CH2NH3 crystals are then obtained by slow evaporation at room temperature. A photograph of the crystals is shown below. Figure 2 As shown.

[0041] The relationship between the types and proportions of raw materials, volatilization temperature, volatilization time and sample number in the initial mixture is shown in Table 1.

[0042] Table 1. Correspondence between samples and raw materials and synthesis conditions

[0043]

[0044]

[0045] Crystal structure analysis of samples 1# to 8#

[0046] The structure and phase composition of samples 1# to 8# were analyzed using single-crystal X-ray diffraction and powder X-ray diffraction methods.

[0047] Diffraction data collection was performed on a Bruker D8 VENTURE CMOS X-ray single-crystal diffractometer from Germany, which uses a 100K Mo Kα radiation source. Data collection and reconstruction were performed using standard APEX II software, and absorption correction was performed based on a multi-scan model. The structure was solved using a direct method, and in F... 2 The structure was then optimized using the Olex2 software package via full-matrix least squares. All atoms in S1 were refined using anisotropic displacement parameters. PLATON was used to check for missing symmetry elements; no symmetry elements were found.

[0048] Powder X-ray diffraction tests were performed on a Bruker D8 X-ray powder diffractometer from Bruker GmbH, Germany. The test conditions were a fixed target, a monochromatic light source of Cu Kα, and a wavelength of [missing information]. The voltage and current are 40kV / 20A, the slits DivSlit / RecSlit / SctSlit are 2.00deg / 0.3mm / 2.00deg respectively, the scanning range is 5~70°, and the scanning step size is 0.02°.

[0049] The single-crystal X-ray diffraction results showed that samples 1# to 8# had the same chemical formula and crystal structure, with the chemical formula O3SCH2NH3, a molecular weight of 111.12, belonging to the monoclinic crystal system, with a space group of Cm and a unit cell parameter of [missing information]. α=γ=90°, β=129.7°~131.7°, Z=2.

[0050] Taking sample 1# as a typical example, its crystal structure data is as follows: α = γ = 90°, β = 130.7°, Z = 2. Its crystal structure is as follows: Figure 1 As shown.

[0051] The powder X-ray diffraction test results show that the peak positions of samples 1# to 8# are basically the same, while the peak intensities are slightly different.

[0052] Taking sample 1# as a typical example, such as Figure 3 As shown, based on the crystal structure resolved by single-crystal X-ray diffraction, the fitted X-ray diffraction pattern is consistent with the X-ray diffraction pattern obtained after grinding sample 1# into powder. The peak positions and peak intensities are consistent, indicating that the obtained sample has high purity.

[0053] Ultraviolet-Visible Transmission Spectroscopy

[0054] The UV-Vis transmission spectrum of sample 1# was measured using an Agilent Technologies Carry 5000 UV-Vis-NIR spectrophotometer, with a scanning range of 190–800 nm. The results are as follows: Figure 4 As shown, this compound exhibits a wide optical transmission range with an optical band gap greater than 6.53 eV. The deep ultraviolet transmission spectrum was measured at room temperature using a McPherson VUVas2000 spectrophotometer, with a measurement wavelength range of 120–210 nm. Figure 5 The ultraviolet absorption edge of this crystal is less than 170 nm.

[0055] Infrared spectroscopy test

[0056] The infrared spectroscopy of sample 1# was performed using a Nicolet iS10 Fourier transform infrared spectrometer from Thermo Fisher Scientific, Inc., USA. The results are as follows: Figure 6 As shown, 3030-3215cm -1 and 1597-1504cm -1 The [NH3] group exhibits stretching and bending vibrations. 2673-2500 cm⁻¹ -1 The several weak absorption bands at 2890-2980 and 1447 cm⁻¹ correspond to the NH stretching vibration of the [NH₃] group. -1 The infrared absorption bands at these locations are attributed to CH stretching and bending vibrations, respectively. From 1168 to 995 cm⁻¹ -1 The absorption bands can be attributed to the vibrations of the [SO3] units. 748 and 1313 cm⁻¹ -1 The absorption band at that location belongs to the CS and CN vibrations.

[0057] Thermogravimetric test

[0058] Thermogravimetric analysis of sample 1# was performed on a Netzsch STA409PC thermogravimetric analyzer from Netzsch Equipment Manufacturing Co., Ltd., Germany. The results are as follows: Figure 7 As shown, by Figure 7 It can be seen that the thermal decomposition temperature of this compound is 187℃.

[0059] Frequency doubling test experiment and results

[0060] The frequency doubling test experiment for sample #1 is as follows: A Q-switched Nd:YAG solid-state laser with a wavelength of 1064 nm was used as the fundamental frequency light to irradiate the test crystal powder. The generated second harmonic intensity was detected by an Ocean Optics Maya2000 Pro spectrometer. The crystal sample, standard sample KDP, and standard sample BBO crystals were ground separately and sieved with standard sieves to separate crystals of different particle sizes, with particle size ranges of 50–74, 74–105, 105–150, 150–200, and 200–280 μm, respectively. The variation of the frequency doubling signal with particle size was observed to determine whether phase matching could be achieved. Under the same test conditions, the second harmonic intensity generated by the sample, standard sample KDP, and standard sample BBO crystals was compared to obtain the relative magnitude of the sample's frequency doubling effect. Using the same test method, the test crystal powder was irradiated with a fundamental frequency light with a wavelength of 532 nm, and the generated second harmonic intensity was detected by an Ocean Optics Maya2000 Pro spectrometer. The variation of the frequency doubling signal with particle size was observed to determine whether phase matching could be achieved. Under the same test conditions, the second harmonic intensity generated by the sample and the standard sample BBO was compared to obtain the relative magnitude of the frequency doubling effect of the sample. The test results show that the frequency doubling signal intensity of the carbamate crystal under 1064nm wavelength laser irradiation is 3.8 times that of the control sample KDP crystal (e.g., ...). Figure 9 Phase matching (e.g.) can be achieved. Figure 8 Under 532nm wavelength laser irradiation, the frequency doubling signal intensity was 0.7 times that of the control sample BBO crystal (e.g., Figure 11 Phase matching (e.g.) can be achieved. Figure 10 ).

[0061] Crystal birefringence test

[0062] The birefringence properties of sample 1# were measured using a ZEISS AXIO Scope 5 polarizing microscope equipped with a Berek compensator. The light source wavelength was 546 nm. The birefringence was calculated using the following formula:

[0063] ΔR(retardation)=|n e -n o |×T=Δn×T

[0064] In the formula, ΔR represents the optical path difference, Δn represents birefringence, and T represents the crystal thickness. The compensated positive and negative rotations provide a relative delay.

[0065] The results are as follows Figure 12 As shown, Figure 12 a and Figure 12 b are microscopic images of the crystal after complete extinction using a Berek compensator. The thickness (T) of the single crystal was measured to be 17.018 μm, corresponding to an optical path difference (ΔR) of 1.025 μm. Figure 12 c). The measured crystal plane was determined to be [missing information] by single-crystal X-ray diffraction analysis. ( Figure 12 d). Based on the above data, the crystal's properties were calculated. The refractive index difference on the crystal plane at a wavelength of 546 nm is 0.06.

[0066] The embodiments described above are provided to enable those skilled in the art to understand and use the invention, and are not intended to limit this application in any way. Any changes or modifications made by those skilled in the art without departing from the scope of the technical solution of this application using the disclosed technical content are equivalent to equivalent implementation cases and fall within the scope of the technical solution.

Claims

1. A second-order nonlinear optical crystal, carbamate, characterized in that, The chemical formula of the crystalline material is O3SCH2NH3, the molecular weight is 111.12, it belongs to the monoclinic crystal system, its space group is Cm, and its unit cell parameters are... α=γ=90°, β=129.7°~131.7°, Z=2, cell volume is 2. A method for preparing carbamate crystals as described in claim 1, characterized in that, The sulfonic acid source, mineralizing agent, and water are mixed and stirred continuously until a clear and transparent solution is obtained. The solution is then evaporated at room temperature to obtain colorless and transparent blocky crystals, which are the target products.

3. A method for preparing the carbamate crystalline material as described in claim 2, characterized in that, The sulfonic acid source is aminomethanesulfonic acid.

4. A method for preparing the carbamate crystalline material as described in claim 2, characterized in that, The mineralizing agent is selected from at least one of lithium chloride, lithium hydroxide, lithium carbonate, lithium nitrate, and lithium acetate.

5. The method for preparing a second-order nonlinear optical crystal material of carbamate according to claim 2, characterized in that, The addition amounts of sulfonic acid source and mineralizer satisfy the following: the molar ratio of S to Li is (10-30):(5-15).

6. The method for preparing a second-order nonlinear optical crystal material of carbamate according to claim 2, characterized in that, The solution evaporates at a temperature of 20–60°C, and the evaporation time is no less than three days.

7. The application of the carbamate crystalline material according to claim 1, characterized in that, The crystal material is used in frequency multiplier generators, optical parametric oscillators, optical parametric amplifiers, and photoelectric rectifiers.

8. The application of the carbamate second-order nonlinear optical crystal material according to claim 7, characterized in that, When saccharic acid second-order nonlinear optical crystal material is used in laser frequency converters, it can output 532nm laser under 1064nm laser irradiation and 266nm laser under 532nm laser irradiation.

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