The crystal structure and molecular conformation of 3,7‐dichlorophenoselenazine

I am indebted to Professor H. Saalfeld, Dr H. Siems and Dr Wedde of the Mineralogisch-Petrographisches Institut, Universit~,t Hamburg, for their helpful discussion, to Dr Siems for his calculation of the values of Table 7, and to Dr Wedde for his careful inspection of the manuscript. The single-crystal diffractometer used for the measurement was made available b,' tee Owens Illinois Co., Toledo, Ohio, USA, who also supported the work financially.