Das EPR-Spektrum des einfach negativen Chrysen-Ions

Abstract

It was the intention of this work to study various molecular orbital approximations (HÜCKEL, MCLACHLAN and AMOS—SNYDER) in the case of the chrysene radical anion with the aid of EPR methods. This molecule is well-suited for such a test because of its low symmetry and strong spin density variation. The six different hfs splitting constants could be determined by means of computer analysis. The experimental results are best described by MCLACHLAN’S method. Nearly the same agreement is obtained by the AMOS—SNYDER method including full annihilation of the spin quartet component in the unrestricted wave function. Both SCF methods predict a negative spin density at the same particular position.