SUPRAMOLECULAR MATERIALS - MOLECULAR PACKING OF TETRANITROTETRAPROPOXYCALIX[4]ARENE IN HIGHLY STABLE FILMS WITH 2ND-ORDER NONLINEAR-OPTICALPROPERTIES

Citation
Pja. Kenis et al., SUPRAMOLECULAR MATERIALS - MOLECULAR PACKING OF TETRANITROTETRAPROPOXYCALIX[4]ARENE IN HIGHLY STABLE FILMS WITH 2ND-ORDER NONLINEAR-OPTICALPROPERTIES, Chemistry (Weinheim), 4(7), 1998, pp. 1225-1234
Citations number
55
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Chemistry
Journal title
ISSN journal
0947-6539
Volume
4
Issue
7
Year of publication
1998
Pages
1225 - 1234
Database
ISI
SICI code
0947-6539(1998)4:7<1225:SM-MPO>2.0.ZU;2-9
Abstract
Highly stable films of tetranitrotetrapropoxycalix[4]arene (9) with se cond-order nonlinear optical (NLO) properties and a noncentrosymmetric structure were obtained by a novel crystallization process at 130-140 degrees C in a de electric field. The packing of 9 in these films was elucidated by a combination of X-ray diffraction, angle-dependent sec ond-harmonic generation, and scanning force microscopy (SFM). The expe rimental results agree well with solid-state molecular dynamics calcul ations for these films. No crystalline phase was observed for nitrocal ix[4]arene derivatives with longer or branched alkyl chains; this expl ains the limited NLO stability of films of these calixarenes. Scanning force microscopy on the aligned films of 9 showed two distinct surfac e lattice structures: a rectangular lattice (a = 9.3, b = 11.7 Angstro m) and a pseudohexagonal lattice (d approximate to 11.4 Angstrom). The combination of these data with the interlayer distance of 8.9 Angstro m (X-ray diffraction) allowed the packing of molecules of 9 in these s tructures to be fully elucidated at the molecular level.