The unpaired spin S=1/2 states which occur at the ends of an S=1 Heisenberg-like antiferromagnetic chain,have been observed recently in low-temperature electron spin-resonance measurements of Ni(C_(2)H_(8)N_(2))_(2)NO...The unpaired spin S=1/2 states which occur at the ends of an S=1 Heisenberg-like antiferromagnetic chain,have been observed recently in low-temperature electron spin-resonance measurements of Ni(C_(2)H_(8)N_(2))_(2)NO_(2)ClO_(4) containing selected impurities.We present here a further study on this topic by far infrared transmission spectra under the magnetic field.The splitting of S=1/2 modes was clearly observed and explained by the interaction of S=1/2 modes at two nearby chains,which can be separated by vacancy-like defect.展开更多
基金Supported by the National Natural Science Foundation of ChinAlexander von Humboldt Foundation of F.R.Germanythe Foundation of Education Division of Chinese Academy of Sciences for Young Scientist.
文摘The unpaired spin S=1/2 states which occur at the ends of an S=1 Heisenberg-like antiferromagnetic chain,have been observed recently in low-temperature electron spin-resonance measurements of Ni(C_(2)H_(8)N_(2))_(2)NO_(2)ClO_(4) containing selected impurities.We present here a further study on this topic by far infrared transmission spectra under the magnetic field.The splitting of S=1/2 modes was clearly observed and explained by the interaction of S=1/2 modes at two nearby chains,which can be separated by vacancy-like defect.