title: Gradual release of strongly bound nitric oxide from Fe₂(NO)₂(dobdc).
abstract: An iron(II)-based metal-organic framework featuring coordinatively unsaturated redox-active metal cation sites, Fe2(dobdc) (dobdc(4-) = 2,5-dioxido-1,4-benzenedicarboxylate), is shown to strongly bind nitric oxide at 298 K. Adsorption isotherms indicate an adsorption capacity greater than 16 wt %, corresponding to the adsorption of one NO molecule per iron center. Infrared, UV-vis, and Mössbauer spectroscopies, together with magnetic susceptibility data, confirm the strong binding is a result of electron transfer from the Fe(II) sites to form Fe(III)-NO(-) adducts. Consistent with these results, powder neutron diffraction experiments indicate that NO is bound to the iron centers of the framework with an Fe-NO separation of 1.77(1) Å and an Fe-N-O angle of 150.9(5)°. The nitric oxide-containing material, Fe2(NO)2(dobdc), steadily releases bound NO under humid conditions over the course of more than 10 days, suggesting it, and potential future iron(II)-based metal-organic frameworks, are good candidates for certain biomedical applications.
authors.affiliation: †Department of Chemistry, University of California, Berkeley, California 94720, United States.
authors.forename: Eric D
authors.initials: ED
authors.lastname: Bloch
authors.affiliation: ∥Center of Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, United States.|‡The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States.
authors.forename: Wendy L
authors.initials: WL
authors.lastname: Queen
authors.affiliation: §Department of Chemistry, NIS, CrisDi, and INSTM Centre of Reference, University of Turin, Via Quarello 15, I-10135 Torino, Italy.
authors.forename: Sachin
authors.initials: S
authors.lastname: Chavan
authors.affiliation: #EaStChem School of Chemistry, University of St Andrews, Purdie Building, St Andrews KY16 9ST, U.K.
authors.forename: Paul S
authors.initials: PS
authors.lastname: Wheatley
authors.affiliation: †Department of Chemistry, University of California, Berkeley, California 94720, United States.
authors.forename: Joseph M
authors.initials: JM
authors.lastname: Zadrozny
authors.affiliation: #EaStChem School of Chemistry, University of St Andrews, Purdie Building, St Andrews KY16 9ST, U.K.
authors.forename: Russell
authors.initials: R
authors.lastname: Morris
authors.affiliation: ∥Center of Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, United States.|∇Department of Chemical Engineering, University of Delaware, Newark, Delaware 19716, United States.|⊥The Bragg Institute, Australian Nuclear Science and Technology Organization, PMB1 Menai, New South Wales, Australia.
authors.forename: Craig M
authors.initials: CM
authors.lastname: Brown
authors.affiliation: §Department of Chemistry, NIS, CrisDi, and INSTM Centre of Reference, University of Turin, Via Quarello 15, I-10135 Torino, Italy.|⊗Southern Federal University, Zorge Street 5, 344090 Rostov-on-Don, Russia.
authors.forename: Carlo
authors.initials: C
authors.lastname: Lamberti
authors.affiliation: §Department of Chemistry, NIS, CrisDi, and INSTM Centre of Reference, University of Turin, Via Quarello 15, I-10135 Torino, Italy.
authors.forename: Silvia
authors.initials: S
authors.lastname: Bordiga
authors.affiliation: †Department of Chemistry, University of California, Berkeley, California 94720, United States.
authors.forename: Jeffrey R
authors.initials: JR
authors.lastname: Long
mesh_terms: D000327:Adsorption; D065546:Drug Liberation; D005290:Ferric Compounds / Q000737:chemistry*; D008958:Models, Molecular; D008968:Molecular Conformation; D009569:Nitric Oxide / Q000737:chemistry*; D009942:Organometallic Compounds / Q000737:chemistry*
chemical_list: D005290:Ferric Compounds; D009942:Organometallic Compounds; C540999:iron nitrido complex; D009569:Nitric Oxide