JPS63205544A - Laser magnetic resonance device - Google Patents

Abstract

PURPOSE:To detect the laser magnetic resonance spectrum of paramagnetic molecules of a short life by providing a pair of comb-shaped electrodes for high-frequency discharge which impress an electric field to the same direction as a magnetostatic direction for measurement to the inside or outside of a measuring pipe in a magnetostatic field for measurement. CONSTITUTION:The electrodes 13 for high-frequency discharge are installed between the measuring pipe 7 and an electromagnet 8. The magnetostatic direction by the electromagnet 8 and the electric field direction of the electrode 13 are made to coincide with each other, by which the instability of low-temp. plasma is prevented as the electrons and ions in the low-temp. plasma does not receive the force in the axial direction of the measuring pipe even in the magnetostatic field. Since the AC magnetic field by a coil 9 for modulation to detect the laser magnetic resonance spectrum with high sensitivity is not shut off by the electrodes 13 which are formed of comb-shape, said magnetic field is effectively impressed to the paramagnetic molecules. The laser magnetic resonance spectrum of the paramagnetic molecules of a short life is detected by detecting a far IR laser 11 radiated from the window 10 by a detecting and amplifying system 12.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a laser magnetic resonance apparatus that is capable of highly efficient production of paramagnetic molecules.

[Conventional technology]

Regarding the paramagnetic molecule generating part of a laser magnetic resonance apparatus, conventionally, "Laser Research" 15. Hirota K. ``Molecular structure of chemical reaction intermediates determined by high-resolution laser spectroscopy'' is discussed in Flies 9 (1985), pp. 674-689. The paramagnetic molecule generator discussed in the above prior art relies on a microwave discharge outside of the static magnetic field for measurement.

[Problem that the invention seeks to solve]

In the above conventional technology, since the paramagnetic molecule generation section and the measurement section are separated, the paramagnetic molecules may attenuate or disappear before they are introduced into the measurement section. There was a problem that it became impossible to measure. The above phenomenon is caused by (1) Traditionally, microwave discharge was used to create paramagnetic molecules, so it was structurally impossible to place the discharge part in a magnetic field, (2) Intermagnetic field discharge (3) Since laser magnetic resonance (LMR) was mainly used for structural analysis of paramagnetic molecules, it was not necessary to place a discharge between magnetic fields.

An object of the present invention is to enable detection of LMR spectra of short-lived paramagnetic molecules by performing high-frequency discharge in a magnetic field.

[Means for solving problems]

The above purpose is to use high-frequency discharge in a static measuring magnetic field to generate low-temperature plasma to generate paramagnetic molecules, to align the discharge electric field direction with the measuring magnetic field direction, and to arrange the high-frequency discharge electrodes in a comb shape. This is achieved by

[Effect]

Since the high-frequency discharge electrode can be made from a pair of thin metal plates such as copper, it can be easily installed between the measurement tube and the magnetic field generating magnet. The electrons and ions in the low-temperature plasma do not receive any force in the axial direction of the measurement tube even in a static magnetic field, and the low-temperature plasma does not become unstable. In addition, in a range where the static magnetic field is not large (several 1000 Gauss), the diffusion of electrons in the measurement tube axis direction becomes smaller due to the precession of the electrons around the direction of the static magnetic field, which reduces the production efficiency of paramagnetic molecules. I can hope to give it to you.

Furthermore, by making the high-frequency discharge electrode comb-shaped instead of a pair of thin plates, the alternating current magnetic field used by the coil used for modulation to detect the LMR spectrum with high sensitivity is blocked by the discharge electrode. It can be applied effectively to paramagnetic molecules without any problems.

〔Example〕

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a longitudinal cross-sectional view of the vicinity of the high-frequency discharge electrode in one embodiment of the laser magnetic resonance apparatus according to the present invention, FIG. 2 is a cross-sectional view of the above-mentioned FIG. 1, and FIG. 3 is a high-frequency discharge in another embodiment. FIG. 4, a longitudinal cross-sectional view of the vicinity of the electrode, is a cross-sectional view of FIG. 3 above. In FIGS. 1 and 2, the carbon dioxide laser 1 is input from g2 of the far-infrared laser gas excitation section 5 of the measurement tube to excite the far-infrared laser gas introduced into the far-infrared laser gas excitation section 5 in advance. . The far-infrared laser oscillates due to resonance between the movable concave mirror 4 and the fixed concave surface ff15. The measurement tube 7, which is also separated from the far-infrared laser gas excitation section 3 by the Priester film 6, is in the static magnetic field for measurement by the electromagnet 8 and the alternating magnetic field by the absorption modulation coil 9. If paramagnetic molecules absorb far-infrared laser, the far-infrared laser output required for one oscillation decreases.

Therefore, if the far-infrared laser 11 emitted from the window 10 is detected by the detection/amplification system 12 while sweeping the static magnetic field for measurement, an LMR spectrum can be obtained without being affected by the lifetime of paramagnetic molecules. High-frequency discharge comb-shaped electrode 13 for generating plasma outside or inside the measurement tube 7
is installed so that the direction of the electric field it generates matches the direction of the magnetic field.

The sample gas 14 is introduced into the measuring tube 7 from the outside.

It is decomposed by high frequency discharge to generate paramagnetic molecules, which are exhausted through the exhaust pipe 15. Now, since the direction of the static magnetic field and the direction of the discharge electric field match, the electrons and ions generated by the discharge are not subjected to force in the axial direction of the measurement tube 7, and the low-temperature plasma is stable, and the low-magnetic field region Rather, the diffusion of electrons in the axial direction of the measuring tube 7 is reduced, and the production efficiency of paramagnetic molecules is improved.

Since the discharge electrode 13 has a comb shape, the alternating current magnetic field generated by the modulation coil 9 for detecting the LMR spectrum with high sensitivity is effectively applied to the paramagnetic molecules without causing any eddy current to flow on the discharge electrode 1S. Ru.

In the other embodiments shown in FIGS. 3 and 4, a comb-shaped electrode 13 for high-frequency discharge is installed inside the measuring tube 7, and the other embodiments are the same as the embodiments described above, and the effects are also the same. be.

〔Effect of the invention〕

As described above, the laser magnetic resonance apparatus according to the present invention includes a laser oscillation section, a static magnetic field for measurement, a measurement tube, and a detection system. By providing a pair of comb-shaped high-frequency discharge electrodes on the inside or outside that apply an electric field in the same direction as the magnetostatic direction for measurement, high-frequency discharge plasma can be created within the measurement magnetic field, resulting in a long service life. This has the effect of being able to detect short paramagnetic molecules.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view of the vicinity of the high-frequency discharge electrode in one embodiment of the laser magnetic resonance apparatus according to the present invention, FIG. 2 is a cross-sectional view of the above-mentioned FIG. 1, and FIG. 3 is a high-frequency discharge in another embodiment. Vertical sectional view near the electrode - FIG. 4 is a diagram showing the cross section of FIG. 3 above. 3...Far-infrared laser gas excitation section, 7...
・Measuring tube. 8... Electromagnet, 11... Far infrared laser, 12... Detection/amplification system, 13... Comb-shaped high frequency discharge electrode.

Claims (1)

[Claims] 1. In a laser magnetic resonance apparatus equipped with a laser oscillation unit, a static magnetic field for measurement, a measurement tube, and a detection system, the static magnetic field for measurement is placed inside or outside of the measurement tube that is within the static magnetic field for measurement. A laser magnetic resonance apparatus characterized in that a pair of comb-shaped high-frequency discharge electrodes are provided to apply an electric field in the same direction.