1. Research Center for Organic Electronics, Yamagata University, 4-3-16 Jonan, Yonezawa 992-8510, Yamagata, Japan
2. Faculty of Education, Art and Science, Yamagata University, 1-4-12 Kojirakawa-machi, Yamagata City 990-8560, Yamagata, Japan
3. Department of Organic Materials Science, Graduate School of Organic Materials Science, Yamagata University, 4-3-16 Jonan, Yonezawa 992-8510, Yamagata, Japan