Magnetic circular dichroism spectrum and magnetic rotation dispersion simultaneous measurement method

Abstract

The invention discloses a magnetic circular dichroism spectrum and magnetic rotation dispersion simultaneous measurement method. Substituting test data of a magnetic circular dichroism spectrum and magnetic rotation dispersion simultaneous measurement device based on a time sequence polarization measurement method into a spectrograph CCD (Charge Coupled Device) receiving light relative intensity principle formula, establishing an equation set, and solving a normalized Stokes parameter average value of sample transmission light; and obtaining a test result according to the relationship between the magnetic circular dichroism and magnetic circular birefringence quantization parameters and the Stokes parameter. According to the test method disclosed by the invention, test results of two characteristics of the magnetic circular dichroism spectrum and the magnetic rotation dispersion of the material can be obtained in one test; the test principle is direct, the test method is simple, rapid and effective, the required device is relatively simple, the actual wave plate retardation function and the spectrometer polarization effect are considered, and a large amount of data is averaged; and the test result is idealized and high in accuracy. The test method is beneficial to integration of related test functions of the composite equipment, and is beneficial to popularization in the related scientific research and test technical field.

Description

Technical Field

[0001] The present invention relates to the field of magnetic circular dichroism spectroscopy and magnetic optical rotation dispersion testing. Specifically, the present invention relates to a method for simultaneously measuring magnetic circular dichroism spectroscopy and magnetic optical rotation dispersion. Background Art

[0002] Linearly polarized light can be expressed as the coherent superposition of left-hand circularly polarized light (LCP) and right-hand circularly polarized light (RCP). If the refractive indices of the medium for left- and right-handed elliptically polarized light are different, when the linearly polarized light passes through the medium, the polarization direction changes. This phenomenon is called circular birefringence (CB) or optical rotation. Usually, some chiral substances have the property of circular birefringence. Since the medium always has a certain absorption of light, if the absorption of the medium for RCP and LCP is different, it is the phenomenon of circular dichroism (CD). The medium can simultaneously have the properties of circular dichroism and circular birefringence.

[0003] Circular birefringence and circular dichroism can be generated by internal factors, such as natural or the medium itself being magnetized with magnetization intensity; they can also be induced by external factors, such as an external magnetic field inducing the magnetization of the medium; or they can be the superposition of these mechanisms. When the medium exhibits circular birefringence and circular dichroism due to the action of a magnetic field in a magnetic field parallel to the light transmission direction, these two phenomena are respectively called magnetic circular birefringence (MCB) and magnetic circular dichroism (MCD). Magnetic circular birefringence is also called the Faraday magneto-optical rotation effect. The direction of magneto-optical rotation is related to the direction of the magnetic field and has nothing to do with the direction of light propagation. When observing along the magnetic field, if the direction of optical rotation of the medium is clockwise, this medium is called a positive rotator; if it is counterclockwise, the medium is called a negative rotator. Setting the magnetic field to zero in the magnetic circular birefringence measurement and magnetic circular dichroism device can often also be used for the measurement of circular birefringence and circular dichroism.

[0004] The correspondence between circular birefringence and circular dichroism and the wavelength of the light wave in the incident medium is called the circular birefringence spectrum and the circular dichroism spectrum. The circular birefringence spectrum and the circular dichroism spectrum are related by the Kramers-Kronig relation. The circular birefringence spectrum manifests as the main body of optical rotation dispersion (ORD), which is named from a phenomenological perspective, while the circular birefringence spectrum is named from a mechanistic perspective. The magnetic circular birefringence spectrum or the Faraday magneto-optical rotation spectrum is also called magnetic optical rotation dispersion (MORD). The magnetic circular dichroism spectrum and the magnetic optical rotation dispersion spectrum are one of the important characteristics of the optical properties of materials and are of great significance for understanding the structure and electronic information of materials.

[0005] In recent years, domestic scholars and research institutions have achieved a series of important results in the field of magnetic circular dichroism spectroscopy and magneto-optical rotation dispersion testing. According to the retrieval of relevant literature and project results, some research mainly focuses on the optimization of the principle and performance improvement of magnetic circular birefringence measurement of monochromatic light, and most research focuses on the analysis of the results of magneto-optical rotation dispersion testing and material characteristics. Currently, the mainstream concept of magnetic circular dichroism spectroscopy testing still measures the absorption of left- and right-handed circularly polarized light by making the left- and right-handed circularly polarized light incident on the sample periodically in time division according to the definition of magnetic circular dichroism (the difference in absorption rates of left- and right-handed light). In terms of magnetic circular dichroism spectroscopy and magneto-optical rotation dispersion measurement instruments, a combination of a retardation modulator (such as a photoelastic modulator or a Soleil compensator) and a monochromator is generally used, and the cost is generally high. In the polarization measurement method, there is a large category of measurement methods called sequential polarization measurement method or time-division polarization measurement method (Russell A. Chipman. Polarized Light and Optical Systems. CRC Press, Taylor & Francis Group. 2019), that is, a series of light flux measurements are carried out in chronological order, and a rotating polarization element is usually used. This method is also narrowly referred to as the θ-scan method or the angular scan method (Xiangshen, Meng, et al. Circularly polarized light to study linear magneto-optics for ferrofluids: θ-scan technique [J]. Measurement Science & Technology, 2018, 29. DOI: 10.1088 / 1361-6501 / aab0e2.). The method of the present invention is based on the sequential polarization measurement method, and uses a linear array CCD (Charge-Coupled Device) spectrometer to detect the relative intensity information of light whose polarization state changes sequentially in time after passing through a rotating wave plate in chronological order. Summary of the Invention

[0006] Object of the Invention: To avoid using a photoelastic modulator (PEM), further simplify the test theory, provide a magnetic circular dichroism spectroscopy and magneto-optical rotation dispersion test method with a simple device, low cost, simple test process and excellent test quality, and be able to obtain the test results of the characteristics of magnetic circular dichroism spectroscopy and magneto-optical rotation dispersion of materials in a single measurement.

[0007] To achieve the above object, the present invention provides the following technical solutions:

[0008] A practical device for simultaneously measuring magnetic circular dichroism spectrum and magneto-optical rotatory dispersion is as follows: Along the light transmission direction, with the light transmission path as the axis, a light source (S), a lens group (L1), a diaphragm (D), a polarizer (P), an electromagnet (EM), a sample cell (SC), a vertical rotating stage (R) for installing a quarter-wave plate (W), a lens group (L2), and a spectrometer (G) are successively connected in series and coaxially placed in sequence, as Figure 1 shown. The magnetic field direction generated by the electromagnet (EM) is parallel to the light transmission direction. A light passing hole is opened along the magnetic field direction in the center of the pole shoes of the electromagnet (EM), the distance between the pole shoes is adjustable, and the electromagnet (EM) is equipped with a power supply whose current magnitude and direction can be adjusted.

[0009] The vertical rotating stage (R) drives the quarter-wave plate (W) to rotate around the axis with the light transmission path as the axis by a controllable stepping motor through mechanical transmission; the rotation angle and speed of the stepping motor on the vertical rotating stage (R) are set and controlled by a test program on the host computer (PC), and the command is sent to the stepping motor controller (C) to drive the stepping motor to execute; the spectrometer (G) sends the collected data to the host computer (PC), and is stored by the test program on the host computer (PC) in a time-sequential manner; the rotation of the controllable stepping motor on the vertical rotating stage (R) and the data acquisition of the spectrometer (G) are synchronously started and ended by the test program on the host computer (PC).

[0010] The time-sequential polarization measurement method is as follows: The fast axis direction of the quarter-wave plate (W) rotates around the axis with the light transmission path as the axis at a uniform angular velocity. The CCD of the spectrometer (G) detects the relative intensity information of the light with the time-sequential change of the polarization state after passing through the rotating quarter-wave plate (W) in a time-sequential manner, and the angle θ between the fast axis direction of the quarter-wave plate (W) and the positive direction of the x-axis of the laboratory coordinate system is equal to the product of the uniform angular velocity ω of the rotation of the fast axis direction of the quarter-wave plate (W) and the time t, that is, the expression θ = ωt; the measured relative intensity data [I ti , t i received by the i-th pixel unit of the CCD of the measured spectrometer (G) is converted into data [I i = ωt i to data [I ti , θ i by the expression θ

[0011] Let the angle α between the polarization direction of the linearly polarized light and the x-axis of the laboratory coordinate system be 0, then the Stokes parameters of the linearly polarized light are Then the Stokes parameters of the polarized light after the horizontally polarized light passes through the sample are The above formula indicates that the test sample simultaneously has (magnetic) circular birefringence and (magnetic) circular dichroism, and the (magnetic) circular birefringence Mueller matrix is In the formula, the delay parameter δ′ = (2πΔn′d) / λ quantifies (magnetic) circular birefringence, where Δn′ = n′ l -n′ r is the difference in the real parts of the refractive indices of LCP and RCP in the medium. The (magnetic) circular dichroism Mueller matrix is In the formula, the attenuation coefficient δ″ = (2πΔn″d) / λ quantifies (magnetic) circular dichroism, where Δn″ = n″ l -n″ r is the difference in the imaginary parts of the refractive indices of LCP and RCP in the medium. If we let T1 = [S0, S1, S2, S3] T , then we have Obviously, The above formula describes the relationship between the (magnetic) circular dichroism and (magnetic) circular birefringence quantization parameters and the Stokes parameters of the polarized light after passing through the sample.

[0012] The light passing through the sample then passes through a rotating wave plate, further through a fixed spectrometer, and finally reaches the spectrometer CCD and is received by the CCD. For a non-ideal achromatic quarter-wave plate, considering the retardation of the wave plate as δ. Looking along the light transmission direction, the fast axis of the wave plate makes an angle θ counterclockwise with the positive direction of the x-axis of the laboratory coordinate system. The Mueller matrix of the wave plate is If the Mueller matrix of the spectrometer is then when the light reaches the spectrometer CCD, the polarization state of the light is T2 = M s ·(M w ·T1).

[0013] The first element of the Stokes parameter T2 of the light reaching the spectrometer CCD is proportional to the light intensity received by the spectrometer CCD In the formula, β is the constant proportionality coefficient, the spectral power distribution incident on the spectrometer slit, and the combined coefficient related to the conversion value of the CCD count value and the light intensity, with different coefficient values for different wavelengths. S0, S1, S2, S3, δ, e 11 , e 12 , e 13 , e 14 are all functions of the wavelength λ.

[0014] The relative intensity data [I ti , θ i of the light received by the i-th pixel unit of the spectrometer CCD obtained by the co-measurement device of magnetic circular dichroism spectrum and magneto-optical rotation dispersion based on time-sequence polarization measurement method is substituted into the relative intensity principle formula of the light received by the i-th pixel unit of the spectrometer CCD: In the formula, the subscript i of the parameter indicates that the parameter corresponds to the wavelength λ of the light received by the i-th pixel unit of the spectrometer CCD i ; β i is the proportionality coefficient; δ i is the known delay function related to the wavelength of the quarter-wave plate; e 11i , e 12i , e 13i and e 14i are the known 4 elements of the first row of the Mueller matrix of the spectrometer; looking along the light transmission direction, θ i is the angle counterclockwise between the fast axis direction of the quarter-wave plate and the positive direction of the x-axis of the laboratory coordinate system; S 0i , S 1i , S 2i , S 3i are the Stokes parameters of the transmitted light of the test sample.

[0015] Traverse the range of [0, 2π] where θ i is located, select 4 θ i values according to certain rules and form a system of equations with the 4 measured values of 4 I i corresponding to these 4 θ ti values I tij (θ ij ) = β i [A 0i S 0i +A 1i (θ ij )S 1i +A 2i (θ ij )S 2i +A 3i (θ ij )S 3i l , j = j1, j2, j3, j4, In the formula, The system of equations contains four equations with j = j1, j2, j3, j4; j1, j2, j3, j4 are 4 θ i ​The data label corresponding to the value; the subscript l is the label of the established system of equations. The average value of the normalized Stokes parameters obtained by solving all systems of equations is In the formula, the parameter with subscript l represents the solution of the l-th system of equations, and k is the number of systems of equations.

[0016] Substitute the average value of the normalized Stokes parameters obtained by solving the said system of equations into the relational expressions between the (magnetic) circular dichroism and (magnetic) circular birefringence quantization parameters and the Stocks parameters, to obtain The magnetic circular dichroism spectrum is The magnetic optical rotation dispersion is In the formula, δ i ″ is the quantization parameter of the magnetic circular dichroism corresponding to the wavelength λ i i is the quantization parameter of the magnetic optical rotation dispersion corresponding to the wavelength λ i i i

[0017] Compared with the existing invention, the advantages of the present invention are:

[0018] A method for simultaneously measuring the magnetic circular dichroism spectrum and the magnetic optical rotation dispersion proposed by the present invention can obtain the test results of two characteristics of the magnetic circular dichroism spectrum and the magnetic optical rotation dispersion of a material in one test; the test principle is direct, the test method is simple, fast and effective, the required device is relatively extremely simple, and the actual wave plate retardation function and the polarization effect of the spectrometer are considered, and a large amount of data averaging processing is carried out; the test results are ideal and highly accurate. The test method of the present invention is beneficial to the integration of relevant test functions of composite equipment and is beneficial to popularization in related scientific research and test technology fields. Brief Description of the Drawings

[0019] Figure 1 is a schematic diagram of the measuring device of the method of the present invention;

[0020] Figure 2 is a test diagram of the magnetic circular dichroism spectrum and the magnetic optical rotation dispersion of an EuCl3·6H2O saturated hydrochloric acid solution contained in a quartz cuvette in a 1.5T magnetic field;

[0021] Description of the Reference Signs in the Drawings

[0022] Figure 1 Among them, S - natural light broad-spectrum light source; L1 - lens group; D - diaphragm; P - polarizer; EM - electromagnet; SC - sample cell; W - 1 / 4 wave plate; R - vertical rotating table; L2 - lens group; G - spectrometer; PC - host computer; C - stepping control motor; x, y, z - identification of the coordinate axes of the laboratory coordinate system. Detailed implementation mode

[0023] The present invention will be further described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0024] As Figure 1 shown, the device used for a method of simultaneously measuring magnetic circular dichroism spectrum and magnetic circular dichroism dispersion provided by an embodiment of the present invention is: a light source (S), a lens group (L1), a diaphragm (D), a polarizer (P), an electromagnet (EM), a sample cell (SC), a vertical rotating table (R) for installing a quarter-wave plate (W), a lens group (L2), and a spectrometer (G) are sequentially connected in series along the light transmission direction with the light transmission path as the axis and coaxially placed in sequence. The magnetic field direction generated by the electromagnet (EM) is parallel to the light transmission direction. A light passing hole is opened in the center of the pole shoes of the electromagnet (EM) along the magnetic field direction, the distance between the pole shoes is adjustable, and the electromagnet (EM) is equipped with a power supply with adjustable current magnitude and direction.

[0025] The vertical rotating table (R) drives the quarter-wave plate (W) to rotate around the axis with the light transmission path as the axis by a controllable stepping motor thereon through mechanical transmission; the rotation angle and speed of the stepping motor on the vertical rotating table (R) are set and controlled by a test program on the host computer (PC), and the command is sent to the stepping motor controller (C) to drive the stepping motor to execute; the spectrometer (G) sends the collected data to the host computer (PC), and is stored by the test program on the host computer (PC) in a time-sequential manner; the rotation of the controllable stepping motor on the vertical rotating table (R) and the data acquisition of the spectrometer (G) are synchronously started and ended by the test program on the host computer (PC).

[0026] The time-sequential polarization measurement method is: the fast axis direction of the quarter-wave plate (W) rotates around the axis with the light transmission path as the axis at a uniform angular velocity, the CCD of the spectrometer (G) detects the relative intensity information of the light with the time-sequential change of the polarization state after passing through the rotating quarter-wave plate (W) in a time-sequential manner, and the angle θ between the fast axis direction of the quarter-wave plate (W) and the positive direction of the x-axis of the laboratory coordinate system is equal to the uniform angular velocity ω of the rotation of the fast axis direction of the quarter-wave plate (W) multiplied by the time t, that is, the expression θ = ωt; the measured relative intensity data [I ti , t i received by the i-th pixel unit of the measured spectrometer (G) CCD is converted into data [I i = ωt i into data [I ti , θ i .

[0027] Preferably, the light source (S) is a halogen lamp with a broad-spectrum continuous spectrum; the lens group (L1) is a collimator; the analyzer (A) is a Glan-Taylor prism; the lens group (L2) is an optical fiber beam expander; the spectrometer (G) is a Rephile FX4000 (365 nm - 701 nm).

[0028] Preferably, the quarter-wave plate is a Wuhan Youguang achromatic quarter-wave plate corresponding to the optical band range of the spectrometer, and its retardance function is δ = (1.08×10 -1 3)λ 5 -(3.93×10 -10 )λ 4 +(5.67×10 -7 )λ 3 -(4.06×10 --4 )λ 2 +0.14λ - 18.45 In the formula, λ is the optical wavelength.

[0029] Preferably, the fast axis direction of the quarter-wave plate (W) is set with a uniform angular velocity of 5° / s, the rotation angle is set to 360°, and the single sampling time of the spectrometer (G) is 0.01 s.

[0030] Preferably, the test sample is a EuCl3·6H2O saturated hydrochloric acid solution, and the container for holding the sample in the sample cell (SC) is a quartz cuvette.

[0031] During the test, the electromagnet (EM) generates a magnetic field of 1.5 T in the space of the sample cell (SC), and the magnetic field direction is parallel and opposite to the light transmission direction.

[0032] Let the angle between the polarization direction of the linearly polarized light and the x-axis of the laboratory coordinate system be α = 0, then the Stokes parameters of the linearly polarized light are Then the Stokes parameters of the polarized light after the horizontal linearly polarized light passes through the sample are The above formula indicates that the test sample simultaneously has circular birefringence and circular dichroism, and the circular birefringence Mueller matrix is In the formula, the retardation parameter δ′ = (2πΔn′d) / λ quantifies the (magnetic) circular birefringence, where Δn′ = n′l - n′r is the difference in the real part of the refractive index of LCP and RCP in the medium. The dichroism Mueller matrix is In the formula, the attenuation coefficient δ″ = (2πAn″d) / λ quantifies the (magnetic) circular dichroism, where Δn″ = n″l -n″ r is the difference between the imaginary parts of the refractive indices of LCP and RCP in the medium. If we let T1 = [S0, S1, S2, S3] T , then we have Obviously,[[]] The above equation describes the relationship between the (magnetic) circular dichroism and (magnetic) circular birefringence quantization parameters and the Stokes parameters of polarized light after passing through the sample.[[]]

[0033] The light passing through the sample then passes through a rotating wave plate, further through a fixed spectrometer, and finally reaches the spectrometer CCD and is received by the CCD. For a non-ideal achromatic quarter-wave plate, considering the retardation of the wave plate as δ. Looking along the light propagation direction, the fast axis of the wave plate makes an angle θ counterclockwise with the positive direction of the x-axis of the laboratory coordinate system, and the Mueller matrix of the wave plate is If the Mueller matrix of the spectrometer is then when the light reaches the spectrometer CCD, the polarization state of the light is T2 = M s ·(M w ·T1).[[]]

[0034] The first element of the Stokes parameter T2 of the light reaching the spectrometer CCD is proportional to the light intensity received by the spectrometer CCD where β is a constant proportionality coefficient, the spectral power distribution incident on the spectrometer slit, and the combined coefficient related to the conversion value of the CCD count value and the light intensity, with different coefficient values for different wavelengths. S0, S1, S2, S3, δ, e 11 , e 12 , e 13 , e 14 are all functions of the wavelength λ.[[]]

[0035] Substitute the relative intensity data [I ti , θ i of the light received by the i-th pixel unit of the spectrometer CCD obtained by the magnetic circular dichroism spectrum and the magneto-optical rotation dispersion co-measurement device based on the time-sequential polarization measurement method into the principle formula of the relative intensity of the light received by the i-th pixel unit of the spectrometer CCD: where the subscript i of the parameter indicates that the parameter corresponds to the wavelength λ of the light received by the i-th pixel unit of the spectrometer CCD i ; β iis the proportionality coefficient; δ i is the known delay function related to the wavelength of the quarter-wave plate; e 11i 、e 12i 、e 13i and e 14i are the known 4 elements in the first row of the Mueller matrix of the spectrometer; looking along the light transmission direction, θ i is the angle counterclockwise between the fast axis direction of the quarter-wave plate and the positive x-axis direction of the laboratory coordinate system; S 0i ,S 1i ,S 2i ,S 3i are the Stokes parameters of the transmitted light of the test sample.

[0036] Divide the [0, 2π] interval of the θ i value into 12 small intervals: the 1st interval [0, π / 6), the 2nd interval [π / 6, π / 3), the 3rd interval [π / 3, π / 2), the 4th interval [π / 2, 2π / 3), the 5th interval [2π / 3, 5π / 6), the 6th interval [5π / 6, π), the 7th interval [π, 7π / 6), the 8th interval [7π / 6, 4π / 3), the 9th interval [4π / 3, 3π / 2), the 10th interval [3π / 2, 5π / 3), the 11th interval [5π / 3, 11π / 6) and the 12th interval [11π / 6, 2π). Extract one θ i value from the 2nd, 3rd, 4th and 5th intervals in sequence, and form a system of equations with the 4 measured I i values corresponding to these 4 θ ti values Among them, In the formula, k is the number of discrete θ i values in each small interval, and is also the number of systems of equations; l is an integer from 1 to k, and is also the label of the established system of equations. Similarly, extract one θ i value from the 8th, 9th, 10th and 11th intervals in sequence, and form a system of equations with the 4 measured I i values corresponding to these 4 θ ti values. The average value of the normalized Stokes parameters obtained by solving all systems of equations is [[ID=B]] In the formula, the parameter with subscript l represents the solution of the lth system of equations, and k is the number of systems of equations.

[0037] Substitute the solution of the system of equations described above into the relationship between the (magnetic) circular dichroism and (magnetic) circular birefringence quantization parameters and the Stokes parameters, and it can be obtained that (Magnetic) circular dichroism spectrum is: (Magneto-)optical rotation dispersion (circular birefringence spectrum) is as follows: where δ i ″ is the quantization parameter of the magnetic circular dichroism corresponding to the wavelength λ i , and δ i is the quantization parameter of the magneto-optical rotation dispersion corresponding to the wavelength λ i .

[0038] The magnetic circular dichroism spectrum and the magneto-optical rotation dispersion diagram as shown in Figure 2 are obtained through computer programming. It should be noted that: the positive and negative of the magnetic circular dichroism spectrum and the magneto-optical rotation dispersion value are related to the direction of the magnetic field setting; the test result is the overall characteristic of the test sample material and the container material. If the characteristic result of the container material can be ignored, the treatment of deducting the characteristic result of the container material may not be done. The above embodiments only list the tests on the selected samples, and the implementation methods in the present invention are equally applicable to the tests of magnetic circular dichroism spectrum and magneto-optical rotation dispersion on other materials. As long as the material has one or both of the (magnetic) circular birefringence and (magnetic) circular dichroism characteristics, and the effective transmitted light intensity information is sufficient to be detected by the spectrometer CCD, the method of the present invention can be used for testing.

[0039] The above is only the specific implementation manner of the present invention, but those skilled in the art should know that the present invention is not limited to the above description. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A method for simultaneously measuring magnetic circular dichroism spectrum and magnetic optical rotation dispersion, characterized in that: The relative intensity data [I ti , θ i of the light received by the i-th pixel unit of the spectrometer (G) CCD obtained by the magneto-circular dichroism spectrum and magneto-optical rotation dispersion co-measurement device based on time-sequence polarization measurement method is substituted into the relative intensity principle formula of the light received by the i-th pixel unit of the spectrometer (G) CCD: In the formula, the subscript i of the parameter represents that the parameter corresponds to the light wavelength λ received by the i-th pixel unit of the CCD of the spectrometer (G); i β i is the proportionality coefficient; δ i is the known delay function related to the wavelength of the quarter-wave plate; e 11i e 12i e 13i e 14i and e are the known four elements of the first row of the Mueller matrix of the spectrometer; Looking along the light transmission direction, θ i is the counterclockwise angle between the fast axis direction of the quarter-wave plate and the positive x-axis direction of the laboratory coordinate system; S 0i , S 1i , S 2i , S 3i are the Stokes parameters of the transmitted light of the test sample; Traverse θ i In the range of [0, 2π] where it is located, select 4 θ values according to certain rules i values and the 4 I i measured values corresponding to these 4 θ ti values to form a system of equations I tij (θ ij ) = β i [A 0i S 0i + A 1i (θ ij )S 1i + A 2i (θ ij )S 2i + A 3i (θ ij )S 3i ) l ,j = j1, j2, j3, j4, In the formula, The system of equations includes four equations with \(j = j_1, j_2, j_3, j_4\); \(j_1, j_2, j_3, j_4\) are data labels corresponding to 4 selected \(\theta\) values according to certain rules; the subscript \(l\) is the label of the established system of equations. The average value of the normalized Stokes parameters obtained by solving all systems of equations is i The system of equations includes four equations with \(j = j_1, j_2, j_3, j_4\); \(j_1, j_2, j_3, j_4\) are data labels corresponding to 4 selected \(\theta\) values according to certain rules; the subscript \(l\) is the label of the established system of equations. The average value of the normalized Stokes parameters obtained by solving all systems of equations is In the formula, the parameter with subscript l represents the solution of the l-th set of equations, and k is the number of sets of equations; Substitute the average value of the normalized Stokes parameters obtained by solving the set of equations into the relationship between the (magnetic) circular dichroism and (magnetic) circular birefringence quantization parameters and the Stocks parameters, and obtain The magnetic circular dichroism spectrum is The magnetic optical rotation dispersion is where, δ i ″ is the quantization parameter of the magnetic circular dichroism corresponding to the wavelength λ i , and δ i ′ is the quantization parameter of the magnetic optical rotation dispersion corresponding to the wavelength λ i .

2. The method for simultaneously measuring magnetic circular dichroism spectrum and magnetic optical rotation dispersion according to claim 1, characterized in that, A practical device for a method for simultaneously measuring magnetic circular dichroism spectrum and magnetic optical rotation dispersion is: along the light transmission direction, with the light transmission path as the axis, a light source (S), a lens group (L1), a diaphragm (D), a polarizer (P), an electromagnet (EM), a sample cell (SC), a vertical rotating table (R) for installing a quarter-wave plate (W), a lens group (L2), and a spectrometer (G) are sequentially connected in series and coaxially placed in turn; The vertical rotating table (R) drives the quarter-wave plate (W) to rotate around the axis with the light transmission path as the axis through mechanical transmission by the controllable stepping motor thereon; the rotation angle and speed of the stepping motor on the vertical rotating table (R) are set and controlled by the test program on the upper computer (PC), and the command is sent to the stepping motor controller (C) to drive the stepping motor to execute; the spectrometer (G) sends the collected data to the upper computer (PC), and is stored in a time-sequence manner by the test program on the upper computer (PC); the rotation of the controllable stepping motor on the vertical rotating table (R) and the data collection of the spectrometer (G) are synchronously started and ended by the test program on the upper computer (PC).

3. A method for simultaneously measuring magnetic circular dichroism spectrum and magnetic circular dichroism dispersion according to claim 1, characterized in that The time-sequence polarization measurement method is as follows: the fast axis direction of the quarter-wave plate (W) rotates at a uniform angular velocity around the axis with the optical transmission path as the axis, and the CCD of the spectrometer (G) detects the relative intensity information of the light with the time-sequence change of the polarization state after passing through the rotating quarter-wave plate (W) in time sequence, and the angle θ between the fast axis direction of the quarter-wave plate (W) and the positive direction of the x-axis of the laboratory coordinate system is equal to the product of the uniform angular velocity ω of the rotation of the fast axis direction of the quarter-wave plate (W) and the time t, that is, the expression θ = ωt; the relative intensity data [I ti , t i of the light received by the i-th pixel unit of the actually measured spectrometer (G) CCD obtained by the time-sequence polarization measurement method is converted into data [I i = ωt i , θ ti according to the expression θ i .

4. A method for simultaneously measuring magnetic circular dichroism spectrum and magnetic circular dichroism dispersion according to claim 2, characterized in that In a practical device for a method for simultaneously measuring magnetic circular dichroism spectrum and magnetic optical rotation dispersion, the magnetic field direction generated by the electromagnet (EM) is parallel to the light transmission direction. A light passing hole is opened in the center of the pole shoe of the electromagnet (EM) along the magnetic field direction, the pole shoe spacing is adjustable, and the electromagnet (EM) is equipped with a power supply with adjustable current magnitude and direction.

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