在MeV二次离子质谱法中的静态极限
Mirjana Sepahyar Lorentzen1, Boštjan Jenčič2, Primož Vavpetič2
1Jožef Stefan Institute Postgraduate School, Jamova 39, 1000 Ljubljana, Slovenia.
Journal of the American Society for Mass Spectrometry
|March 7, 2025
概括
二次离子质谱学 (SIMS) 的静态极限通常适用于MeV-SIMS,但消失截面显示出意想不到的能量依赖性. 本研究探讨了MeV-SIMS适用于有机分子分析的应用性和离子动力学.
科学领域:
- 表面科学是一门学科.
- 质谱测量质量谱测量
- 材料分析 材料分析
背景情况:
- 在二次离子质谱学 (SIMS) 中的静态极限定义了用于分析处女表面的值束流动性.
- 常见的SIMS技术在大约10^12离子/厘米^2.2.的值以下工作.
- MeV-SIMS利用了MeV能量初级离子,依靠电子激发进行二次离子脱吸.
研究的目的:
- 调查 MeV-SIMS. 中静态极限的适用性.
- 了解MeV-SIMS.中的有机目标的消失截面的能量依赖.
- 在长时间的MeV-SIMS轰炸中分析二次离子质谱的动态.
主要方法:
- 使用MeV-SIMS测量有机目标的消失截面.
- 用三种不同的MeV能量级别用初级离子对目标进行轰炸.
- 随着时间的推移对二次离子产量的监测,以研究光谱动态.
主要成果:
- 静态SIMS模式通常适用于MeV-SIMS和普通SIMS的类似流动范围.
- 消失截面显示出对初级离子束能量的依赖,具有10 MeV以下的意想不到的特征.
- 在长时间的轰炸中监测了二次离子产量和碎片化模式,有助于分子识别.
结论:
- MeV-SIMS可以在静态SIMS模式内运行,从而实现表面敏感分析.
- 消失截面的能量依赖性需要仔细考虑,特别是在较低的MeV能量下.
- 对二次离子动态的分析为MeV-SIMS中的分子碎片化和识别提供了宝贵的见解.
相关概念视频
Mass Analyzers: Overview
558
The mass analyzer is a crucial component of the mass spectrometer. In the ionization chamber, the vaporized sample is bombarded with a high-energy electron beam to generate a radical cation and further fragment into neutral molecules, radicals, and cations. A series of negatively charged accelerator plates accelerate the cations into the mass analyzer. The mass analyzer separates ions according to their mass-to-charge (m/z) ratios and then directs them to the detector. The common types of mass...
558
Mass Spectrometers
5.0K
This lesson details the instrumentation of a mass spectrometer—a physical instrument to perform mass spectrometry on analyte molecules and record the characteristic mass spectra. This is achieved via three chief functions:
5.0K
Electrospray Ionization (ESI) Mass Spectrometry
692
Higher molecular weight biomolecules are nonvolatile compounds that may decompose before ionizing or vaporizing during mass analysis with conventional electron impact ionization methods. Accordingly, electrospray ionization (ESI) is the favored method for vaporizing and ionizing biomolecules as it circumvents rapid fragmentation and enables the recording of mass signals for the entire biomolecule.
ESI utilizes electrical energy to transfer ions from the liquid phase of the sample into the...
ESI utilizes electrical energy to transfer ions from the liquid phase of the sample into the...
692
Mass Analyzers: Common Types
540
The quadrupole mass analyzer consists of four cylindrical metal rods arranged in a diamond carrying a DC voltage and a radio-frequency AC voltage. The motion of ions through the quadrupole depends on the field strength, causing only ions of a certain m/z to resonate successfully and strike the detector at a given field strength. Though the transmission rate for these analyzers is high, the exact elemental composition of the sample is not determined because of low resolution; however, they are...
540
High-Resolution Mass Spectrometry (HRMS)
1.2K
The resolution of a mass spectrometer depends on the efficiency of separating ions with different ion masses. The mass of an atom is approximated to the sum of the masses of protons and neutrons inside, considering the masses of protons and neutrons as equal. However, the masses of the proton (1.6726 × 10−24 g) and neutron (1.6749 × 10−24 g) are not truly equal. There is a minor error in the expression of atomic masses relative to the simplest atom of hydrogen. For...
1.2K
Mass Spectrometry: Overview
4.0K
Mass spectrometry is an analytical technique used to determine the molecular mass and molecular formula of a compound. The basic principle of mass spectrometry is to generate ions from the analyte molecule and measure these ion abundances against their molecular mass. One common type of ionization, known as electrospray ionization or EI, bombards the analyte molecules in the gas phase with high-energy electron beams. The electron beams displace an electron from the molecule and leave...
4.0K


