The temperature dependence of the optical nonlinear susceptibility of sodium nitrite

✍ Scribed by H. Vogt; H. Happ

• Publisher: John Wiley and Sons
• Year: 1971
• Tongue: English
• Weight: 505 KB
• Volume: 44
• Category: Article
• ISSN: 0370-1972
• DOI: 10.1002/pssb.2220440122

✦ Synopsis

Abstract

Information about the order‐disorder transition of NaNO~2~ is obtained from the temperature dependence of the optical nonlinear susceptibility χ^(2)^. The decrease of χ^(2)^(T) in the ferroelectric phase can be related to increasing rotational motion of the NO‐ions. While χ^(2)^ indicates the degree of order within the NO‐sublattice, the spontaneous polarization P~s~ may be regarded as an order parameter of the Na^+^‐sublattice. The difference between P~s~(T) and χ^(2)^(T) is explained by a different order‐disorder behaviour of the Na^+^‐and the NO‐ions.