Article | REF: K1015 V1

Ultraviolet spectrum constants

Author: Gilbert DANA

Publication date: May 10, 2001

You do not have access to this resource.
Click here to request your free trial access!

Already subscribed? Log in!


Overview

Français

Read this article from a comprehensive knowledge base, updated and supplemented with articles reviewed by scientific committees.

Read the article

AUTHOR

  • Gilbert DANA: Former student at the École normale supérieure - Former professor at Pierre-et-Marie-Curie University (Paris VI)

 INTRODUCTION

Spectroscopic methods are physical study procedures involving energy exchange phenomena between matter and electromagnetic radiation. This may involve the absorption or emission of light, the "light" being in or outside the visible part of the spectrum. These exchanges involve well-defined energy levels in matter, and therefore its quantification. By absorbing a photon with an energy corresponding to the difference between two specific energy levels, the molecule is brought into various excited states. The lowest-energy eigenlevel is called the ground state.

Outside an intense magnetic field, there are three ways for the molecule to store absorbed energy: by decreasing values, electronic energy , vibrational energy , rotational energy :

ΔE = ΔE 1 + ΔE 2 + ΔE 3

Electron energy quanta are the largest and are located in the UV-visible range. They correspond to the promotion of an electron from an orbital occupied in the ground state (bonding or non-bonding orbital) to an anti-bonding orbital. They therefore have an order of magnitude corresponding to the energy of a bond. Consequently, they are capable of breaking such a bond. For example, bichlor

You do not have access to this resource.

Exclusive to subscribers. 97% yet to be discovered!

You do not have access to this resource.
Click here to request your free trial access!

Already subscribed? Log in!


The Ultimate Scientific and Technical Reference

A Comprehensive Knowledge Base, with over 1,200 authors and 100 scientific advisors
+ More than 10,000 articles and 1,000 how-to sheets, over 800 new or updated articles every year
From design to prototyping, right through to industrialization, the reference for securing the development of your industrial projects

This article is included in

Characterization and properties of matter

This offer includes:

Knowledge Base

Updated and enriched with articles validated by our scientific committees

Services

A set of exclusive tools to complement the resources

Practical Path

Operational and didactic, to guarantee the acquisition of transversal skills

Doc & Quiz

Interactive articles with quizzes, for constructive reading

Subscribe now!

Ongoing reading
Ultraviolet spectrum constants