Yang, Wen-Wen; Zhong, Yu-Wu; Yoshikawa, Shinpei; Shao, Jiang-Yang; Masaoka, Shigeyuki; Sakai, Ken; Yao, Jiannian; Haga, Masa-Aki Inorganic Chemistry, 2012 , vol. 51, # 2 p. 890 - 899