Synthesis and Crystal Structure of E-4,4’-Bis(N,N-di-n-butylamino)stilbene

1 INTRODUCTION Two-photon absorption is a subject which attracts fast-growing interest in chemistry, photonics, and biological imaging fields in the past decades[1]. The two-photon techniques have wide applications, for example, optical power limiting[2], two-photon opti- cal memory[3], two-photon confocal imaging[4] and up-conversion laser[5]. Especially recently, the inte- rest has gradually been focused on studying two- photon initiated photopolymerization (TPIP) and exploring some pe…