TY - JOUR
T1 - Third-order nonlinear optical properties of trigonal, rhombic and bow-tie graphene nanoflakes with strong structural dependence of diradical character
AU - Yoneda, Kyohei
AU - Nakano, Masayoshi
AU - Kishi, Ryohei
AU - Takahashi, Hideaki
AU - Shimizu, Akihiro
AU - Kubo, Takashi
AU - Kamada, Kenji
AU - Ohta, Koji
AU - Champagne, Benoît
AU - Botek, Edith
PY - 2009/10/8
Y1 - 2009/10/8
N2 - Using broken-symmetry hybrid density functional theory, we investigate the relationship between the diradical character and the second hyperpolarizabilities, γ, for a trigonal graphene nanoflake (trigonal GNF) and two types of GNFs with rhombic and bow-tie structures composed of two trigonal GNFs. It is shown that the GNF architecture has a large impact on the diradical character and subsequently on γ. In particular, γ of rhombic GNF with intermediate diradical character is found to be more than twice as large as that of bow-tie GNF with nearly pure diradical character. Then, switching from the singlet to triplet state rhombic GNF exhibits a significant reduction of γ.
AB - Using broken-symmetry hybrid density functional theory, we investigate the relationship between the diradical character and the second hyperpolarizabilities, γ, for a trigonal graphene nanoflake (trigonal GNF) and two types of GNFs with rhombic and bow-tie structures composed of two trigonal GNFs. It is shown that the GNF architecture has a large impact on the diradical character and subsequently on γ. In particular, γ of rhombic GNF with intermediate diradical character is found to be more than twice as large as that of bow-tie GNF with nearly pure diradical character. Then, switching from the singlet to triplet state rhombic GNF exhibits a significant reduction of γ.
UR - http://www.scopus.com/inward/record.url?scp=70349484872&partnerID=8YFLogxK
U2 - 10.1016/j.cplett.2009.09.047
DO - 10.1016/j.cplett.2009.09.047
M3 - Article
AN - SCOPUS:70349484872
SN - 0009-2614
VL - 480
SP - 278
EP - 283
JO - Chemical Physics Letters
JF - Chemical Physics Letters
IS - 4-6
ER -