K. Ogawa et al., STRUCTURE OF 8-(4-ACETYLPHENYL)-1,4-DIOXA-8-AZASPIRO[4.5]DECANE - A NEW POTENTIAL NONLINEAR-OPTICAL MATERIAL, Acta crystallographica. Section C, Crystal structure communications, 50, 1994, pp. 95-97
The crystals of the title compound (APDA), C15H19NO3. which belong to
a non-centrosymmetric space group Pna2(1), show significant second har
monic generation efficiency and no absorption for light with a wavelen
gth longer than 400 nm.