title: Reversible capping/uncapping of phosphorous-centered Keggin-type polyoxoniobate clusters.
abstract: Caps in α-Keggin-type polyoxometalates [PM2Nb12O40](9-) (M: Nb[double bond, length as m-dash]O or V[double bond, length as m-dash]O) can be removed in basic condition to produce uncapped [PNb12O40](15-). Transmetalation or capping occurs from the reaction of [PNb14O42](9-) or [PNb12O40](15-) with either Sb2O3 or V2O5 to form [PSb2Nb12O40](9-) or [PV2Nb12O42](9-), respectively.
authors.affiliation: Department of Chemistry, University of California, Davis One Shields Ave. Davis, CA 95616, USA. junghoson@gmail.com.
authors.forename: Jung-Ho
authors.initials: JH
authors.lastname: Son
authors.forename: William H
authors.initials: WH
authors.lastname: Casey