Introduction

Spectroscopy encompasses a range of techniques used to analyze the interaction of light with matter, offering insights into the composition and structure of substances. The general principle involves measuring the absorption, emission, or scattering of light by molecules or atoms.

Atomic Absorption Spectroscopy (AAS) is based on the absorption of light by free atoms in the gas phase, with key components including a light source, atomizer (such as a graphite furnace or hydride generation system), monochromator, and detectors.

Flame Emission Spectroscopy (FES) and Plasma Emission Spectroscopy (PES) are types of Atomic Emission Spectroscopy (AES), where atoms or ions in an excited state emit light at characteristic wavelengths, with Inductively Coupled Plasma (ICP) as a common excitation source offering high sensitivity and multi-element capabilities.

A spectrophotometer measures the intensity of light at different wavelengths, crucial for both qualitative and quantitative analysis. X-ray diffraction (XRD) involves directing X-rays at a crystalline material and analyzing the diffracted rays to deduce the material's atomic structure.

These techniques collectively provide powerful tools for material identification, concentration determination, and structural analysis across diverse scientific and industrial applications.

Objectives

After going through this unit you will be able to:

1. explain the atomic absorption spectroscopy;

2. define atomic emission spectroscopy with the flame mission;

3. define various techniques: A. Plasma emission spectrometry B. Inductively coupled plasma C. ICP instrumentation

 D. Spectrophotometer E.  X – ray diffraction- principles.