质谱如何与其他光谱技术不同？

质谱补充了其他光谱技术所提供的信息。然而，它在几个方面是不同的optical spectroscopic methods of analysis此类差异将在本文中突出显示。

Optical Spectroscopic Techniques

光学光谱技术提供样品中存在的光吸收或发射物种的定性和定量信息。这种光谱技术的基础是电磁辐射与物质的相互作用。相互作用对于每个物种特异性并且随着入射电磁辐射的波长而变化。然而，仅提供有用的细节仅提供每个分子或离子物质的波长特征。在进行质量光谱技术之前，简要提及一些流行光学光谱技术提供的典型信息，这将不会出现不合适：

UV - Vis光谱

Qualitative and quantitative estimation of molecules containing chromophoric groups and those having different degrees of conjugation. Trace metals quantification through metal-ligand complex reactions is another major application.

FT – IR Spectroscopy

具有不同官能团的化合物的鉴定和结构构象。BY和大型主要用于材料表征组件的定性构象。

Fluorescence Spectroscopy

发射强度测量记录在与激发波长不同的波长处。在暴露于下波长入射光后的时间间隙后吸收后，样品发射更高波长的光。

Atomic Absorption Spectroscopy

Quantitative determination of trace metals in different sample matrices by absorption of light by atoms in ground state in the atomic flame or graphite furnace at specific wavelengths generated by same metals present in the light source.

ICP – OES

Emission of light at specific wavelength by sample elements introduced in the high temperature plasma source

Mass spectroscopy

质谱与光学光谱明显不同，并且在样品分子提供更多细节。

The sample molecules in the vapour phase are ionized by impact with high energy electrons. The charged molecules on passing through magnetic and/or electrostatic field are deflected along a circular path in relation to their mass to charge ratio (m/z). Ionization by displacement of a single electron results in a molecular ion. Due to its instability the molecular ion can disintegrate to even smaller mass fragments. The deflected ionic beams get accelerated along different circular paths according to the m/z ratios of the ionized species. Scanning of the magnetic and or electrostatic field will result in different paths for different fragmented ions which will reach the detector at different points and generate detector signals.

来自光学光谱技术的质谱的主要差异是：

• 分子种的特征在于它们的质量对电荷比率，而吸收和发射的波长在光学技术中表征分子或离子物质。
• Accurate determination of molecular weight of the molecule or ionic mass of ions of interest in addition to their identification.
• Structural elucidation and molecular formula of a compound
• Isotopic abundance of different isotopes constituting the molecule

It can be seen that Mass Spectroscopy provides a wealth of information which is not possible from any single spectroscopic technique. The scope of applications is further extended through hyphenation with other techniques such as GC, LC or FT-IR.