什么是光谱学

一种分析技术，用於鉴别化学元素和化合物，测量物质在外部能源的激发下，吸收或发射电磁波谱（包括γ射线、X射线、紫外辐射、可见光、红外辐射、微波以及无线电频率的辐射）中特徵波长的辐射能量，从而阐明其原子和分子结构。所用的仪器是分光镜（用於直接观察）和摄谱仪（用於记录光谱）。实验包括一个光源、一块用来形成光谱的棱镜或光栅、用来观察或记录光谱细节的探测器（视觉的、光电的、测辐射的或者摄影的）、测量波长和强度的装置以及对测得的量作出解释以识别它的化学身分，或给出关於它的原子和分子结构的线索。19世纪中叶用光谱技术分析太阳光谱而发现了氦、铯和铷。专门的光谱技术有拉曼光谱（参阅Raman, Chandrasekhara Venkata）、核磁共振、原子核四极矩共振、动态反射光谱、微波和γ射线光谱，以及电子自旋共振。亦请参阅mass spectrometry、spectrophotometry。

spectroscopy

Branch of analysis devoted to identifying elements and compounds and elucidating atomic and molecular structure by measuring the radiant energy absorbed or emitted by a substance at characteristic wavelengths of the electromagnetic spectrum (including gamma ray, X ray, ultraviolet, visible light, infrared, microwave, and radio-frequency radiation) on excitation by an external energy source. The instruments used are spectroscopes (for direct visual observation) or spectrographs (for recording spectra). Experiments involve a light source, a prism or grating to form the spectrum, detectors (visual, photoelectric, radiometric, or photographic) for observing or recording its details, devices for measuring wavelengths and intensities, and interpretation of the measured quantities to identify chemicals identifications or give clues to the structure of atoms and molecules. Helium, cesium, and rubidium were discovered in the mid-19th century by spectroscopy of the sun's spectrum. Specialized techniques include Raman spectroscopy (see Chandrasekhara Venkata Raman), nuclear magnetic resonance (NMR), nuclear quadrupole resonance, dynamic reflectance spectroscopy, microwave and gamma ray spectroscopy, and electron spin resonance (ESR). See also mass spectrometry, spectrophotometry.