Spectroscopy 101
Welcome to the fascinating world of molecular spectroscopy. Learn how light unlocks the secrets of matter.
What is Spectroscopy?
Ideally, spectroscopy is the study of the interaction between matter and electromagnetic radiation. Historically, spectroscopy originated through the study of visible light dispersed according to its wavelength, by a prism.
In simple terms: Spectroscopy is the science of using light to measure chemicals.
By analyzing the light that is absorbed, emitted, or scattered by a sample, we can determine:
- Identity: What is it?
- Concentration: How much is there?
- Structure: How are the atoms arranged?
Core Concepts
Light & Matter
Spectroscopy studies the interaction between light (electromagnetic radiation) and matter. Each chemical substance interacts with light in a unique way.
The Spectrum
When light interacts with a sample, significantly more information is returned than just color. We get a "spectrum" - a plot of intensity vs. wavelength.
Identification
Like a human fingerprint, every molecular structure produces a unique spectral pattern. By matching this pattern against a library, we identify the substance.
Quantification
The intensity of the signal is directly proportional to the concentration (Beer-Lambert Law). This allows us to measure "how much" of a substance is present.
Video Lessons
Educational content from Khan Academy®
FTIR Spectroscopy Lessons
Infrared Spectroscopy Overview
IR Spectroscopy Basics
Introduction to Infrared Spectroscopy
IR Spectroscopy Fundamentals
IR Spectrum Analysis
Interpreting IR Spectra
Functional Groups in IR
IR Spectroscopy Practice
Advanced IR Techniques
IR Spectroscopy Applications
IR Problem Solving
Content provided by Khan Academy®
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Major Techniques
The three pillars of vibrational spectroscopy
FT-IR Spectroscopy
Fourier Transform Infrared SpectroscopyThe "fingerprinting" technique of the chemical world. It identifies chemical bonds in a molecule by producing an infrared absorption spectrum.
Raman Spectroscopy
Raman Scattering TechniqueA non-destructive scattering technique that provides detailed information about chemical structure, phase and polymorphy, crystallinity and molecular interactions.
NIR Spectroscopy
Near-Infrared SpectroscopyUses the near-infrared region of the electromagnetic spectrum. It is widely used for quantitative analysis and process control.