Two colorful applications of the PPP method

✍ Scribed by K. Balasubramanian

• Book ID: 104582800
• Publisher: John Wiley and Sons
• Year: 1990
• Tongue: English
• Weight: 770 KB
• Volume: 37
• Category: Article
• ISSN: 0020-7608
• DOI: 10.1002/qua.560370415

✦ Synopsis

Abstract

Two different color‐related applications of the Pariser‐Parr‐Pople method are described. The first one deals with an explanation of the UV‐visible absorption spectrum of the curcumin pigment in turmeric and the color change of curcumin upon addition of OH^−^. The other application deals with blue and red shifts in poly‐diacetylene to polybutatriene transformation. The applications of the FEMO and PPP methods to curcumin facilitate assignment of the two observed bands of curcumin (UV and visible) to the π → π* (UV) and n → π* (visible) transitions, respectively. A graph‐theoretical formulation of the PPP method is also considered.