Väriäityskäyrät

Väriäityskäyrät, also known as absorption spectra or transmission spectra, are graphical representations that depict how a substance absorbs or transmits light at different wavelengths. These curves are fundamental tools in various scientific fields, including chemistry, physics, and biology. The horizontal axis typically represents the wavelength of light, usually measured in nanometers (nm), while the vertical axis shows either the absorbance or the transmittance.

Absorbance refers to the amount of light that is absorbed by the sample at a specific wavelength. Transmittance, on the other hand, indicates the fraction or percentage of light that passes through the sample. These two quantities are inversely related, often expressed by the equation A = -log(T), where A is absorbance and T is transmittance.

Each chemical substance has a unique väriäityskäyrä that acts as a spectral fingerprint. This uniqueness arises from the specific electronic transitions and molecular vibrations within the substance, which dictate which wavelengths of light are absorbed. By analyzing the pattern of peaks and troughs in the väriäityskäyrä, scientists can identify unknown compounds, determine their concentration, and study their structural properties. Spectrophotometry is the primary technique used to obtain these curves, employing instruments called spectrophotometers.