title: Delayed luminescence induced by complex domains in water and in TEOS aqueous solutions.
abstract: Many recent studies on water have conjectured a complex structure composed of hydrogen bonded low- and high-density domains. In this work the structure of pure water and aqueous solutions of silica gel (TEOS) has been investigated by using delayed luminescence, which has previously shown a significant increase in aqueous salt solutions where low-density domain formation is expected. Photon emission shows an Arrhenius trend with an activation energy in water-TEOS solutions larger than in pure water and salt-water solutions. Moreover, delayed photon emission decay shows an intrinsic lifetime of about 5 μs both in solutions and in pure water that, along with secondary lifetimes induced by the presence of TEOS, could be related to the formation of different domains.
authors.affiliation: Dipartimento di Ingegneria e Scienze Applicate, Università di Bergamo, viale Marconi 5, Dalmine, Italy. salesi@unibg.it.
authors.forename: C
authors.initials: C
authors.lastname: Colleoni
authors.affiliation: Istituto Nazionale di Fisica Nucleare, Sezione di Napoli, via Cinthia, Naples, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Esposito
authors.affiliation: Laboratori Nazionali del Sud, Istituto Nazionale di Fisica Nucleare, Catania, Italy.
authors.forename: R
authors.initials: R
authors.lastname: Grasso
authors.affiliation: Laboratori Nazionali del Sud, Istituto Nazionale di Fisica Nucleare, Catania, Italy and Facoltà di Ingegneria e Architettura, Università di Enna "Kore", Enna, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Gulino
authors.affiliation: Laboratori Nazionali del Sud, Istituto Nazionale di Fisica Nucleare, Catania, Italy and Dipartimento di Fisica e Astronomia, Università di Catania, Catania, Italy.
authors.forename: F
authors.initials: F
authors.lastname: Musumeci
authors.affiliation: Dipartimento di Ingegneria e Scienze Applicate, Università di Bergamo, viale Marconi 5, Dalmine, Italy. salesi@unibg.it.
authors.forename: D
authors.initials: D
authors.lastname: Romeli
authors.affiliation: Dipartimento di Ingegneria e Scienze Applicate, Università di Bergamo, viale Marconi 5, Dalmine, Italy. salesi@unibg.it.
authors.forename: G
authors.initials: G
authors.lastname: Rosace
authors.affiliation: Dipartimento di Ingegneria e Scienze Applicate, Università di Bergamo, viale Marconi 5, Dalmine, Italy. salesi@unibg.it and Istituto Nazionale di Fisica Nucleare, Sezione di Milano, via Celoria 16, Milan, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Salesi
authors.affiliation: Laboratori Nazionali del Sud, Istituto Nazionale di Fisica Nucleare, Catania, Italy and Dipartimento di Fisica e Astronomia, Università di Catania, Catania, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Scordino