Atomispektroskopiaa

Atomispektroskopiaa, often referred to in English as atomic spectroscopy, is a branch of analytical spectroscopy that studies the interaction of light with atoms to determine elemental composition and concentration in samples. It relies on electronic transitions between discrete energy levels in neutral atoms or ions, producing characteristic wavelengths that act as fingerprints for elements.

Principles of atomispektroskopiaa involve either absorption or emission of light by atoms. When light at specific wavelengths passes through a sample containing free atoms, certain wavelengths are absorbed proportionally to the element’s concentration. Conversely, excited atoms emit light at characteristic wavelengths as they return to lower energy levels. The resulting spectra enable qualitative identification and quantitative analysis, with techniques grouped into absorption, emission, and fluorescence approaches.

Major techniques include atomic absorption spectroscopy (AAS), which measures the attenuation of light by atoms in a flame or graphite furnace; atomic emission spectroscopy (AES), which analyzes light emitted by excited atoms, as in inductively coupled plasma optical emission spectrometry (ICP-OES) or flame/graphite furnace emission; and laser-induced breakdown spectroscopy (LIBS), which uses a laser to create a microplasma and analyzes the emitted light. Atomic fluorescence spectrometry (AFS) is another related method that detects fluorescence from excited atoms.

Instrumentation typically comprises a light source, a wavelength selector, a detector, and a sample introduction system. Calibration uses standards or standard addition, and data processing converts signal intensity to concentration. Quality control relies on certified reference materials and method validation.

Applications span environmental monitoring, clinical and toxicology analysis, metallurgy, geology, and food safety. Advantages include high sensitivity for many elements and relatively simple sample preparation, while limitations involve matrix effects, spectral interferences, and ionization issues.