Molecular photoreaction test method

Abstract

The invention relates to the field of spectrochemistry and discloses a molecular photoreaction test method. A sample solution is injected into a solution storage poll, and typical flow velocities range from 0.05 to 0.25 ml / min; voltage is applied to electrodes in different areas of an electrode disk to make a piezoelectric ceramic ring corresponding to an electrode vibrate with typical vibration frequencies ranging from 20 to 80 MHz; droplets are ejected to a vacuum chamber and form an ion pack under effects of an ionizer, the ion pack deflects in a first deflector and further forms ion beam current under effects of a vacuum pump group, the ion beam current passes through a mass filter and deflects again by a second deflector, sequentially passes through a first ion buncher, a first ion trap and a second ion buncher and reaches a second ion trap; buffer gas pulses are supplied to the second ion trap, and the air pressure in the second ion trap is increased in a short time; after 0.5 milliseconds, the light emitted by an optical parametric oscillator irradiates the ions in the second ion trap, and a photoreaction happens to the ions; and the products of the ion photoreaction enter atime-of-flight mass spectrometry to obtain related photoreaction information.

Description

technical field [0001] The invention relates to the field of spectrochemistry, in particular to a molecular photoreaction test method that uses optical parameter oscillation to dissociate ions with high-efficiency infrared light. Background technique [0002] Mass spectrometry is a common method for studying the mass characteristics of different molecules in materials. It is usually necessary to atomize the solution containing the sample to be tested into a vacuum environment, and use devices such as charge detectors to study the ion beam current of the molecules to be tested in the vacuum environment. Combining mass spectrometry with an adjustable infrared laser, it is possible to record the vibrational spectrum of mass-selected ions through wavelength-dependent infrared multiphoton dissociation spectroscopy. In the test experiment, it is necessary to detect changes in the charge-to-mass ratio of ions. Optical parametric oscillation is a coherent light source with tunable w...

AI Technical Summary

Problems solved by technology

Defect 1 of the existing technology: the output of optical parametric oscillation is difficult to realize the multi-photon absorption process. For pulsed optical parametric oscillation, short pulses on the order of nanoseconds hinder the vibration redistribution process in the molecule, thereby limiting the photons that can be absorbed , and for the continuous band optical parametric oscillation, the relatively weak power limits the photon absorption rate. Due to the above limitations, the efficiency of infrared photodissociation of ions by optical parametric oscillation is low; prior art defect two: a certain Some samples have different chemical structures in different layers in the solution. In some experiments, only the components near the liquid surface in the sample solution need to be analyzed. The general spraying method will cause samples with different structures in the solution to mix, which will interfere with subsequent experiments; Defect 3 of the prior art: In some prior art, the vibration of the piezoelectric ceramic material is used to generate and eject the liquid droplets of the sample solution, and the direction is difficult to change. In some experiments, it is necessary to constantly adjust the position of the injector to achieve the change of liquid The purpose of the drop ejection direction, the operation is relatively cumbersome, and the fourth defect of the prior art: the voltage drive circuit of the ion trap of the prior art is easily affected by factors such as the fluctuation of the amplifier gain and the temperature drift, which causes the vibration frequency of the ions in the ion trap to fluctuate , which affects the accuracy of the experiment, the described method of molecular photoreaction testing can solve the problem

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