Journal of Solid State Chemistry 178 (2005) 314–320 Intercalation of cyclic ketones into vanadyl phosphate Vı´teˇzslav Zima a,Ã , Kla´ ra Mela´ nova´ a , Ludvı´k Benesˇ a , Miroslava Trchova´ b , Jirˇı´ Dybal b a Joint Laboratory of Solid State Chemistry, Institute of Macromolecular Chemistry of Academy of Sciences, University of Pardubice, Studentska ´ 84, CZ-532-10 Pardubice, Czech Republic b Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic, Heyrovsky´ Sq. 2, 162 06 Prague 6, Czech Republic Received 24 September 2004; received in revised form 5 November 2004; accepted 11 November 2004 Abstract Intercalation compounds of vanadyl phosphate with cyclic ketones (cyclopentanone, cyclohexanone, 4-methylcyclohexanone, and 1,4-cyclohexanedione) were prepared from corresponding propanol or ethanol intercalates by a molecular exchange. The intercalates prepared were characterized using powder X-ray diffraction and thermogravimetric analysis. The intercalates are stable in dry environment and decompose slowly in humid air. Infrared and Raman spectra indicate that carbonyl oxygens of the guest molecules are coordinated to the vanadium atoms of the host layers. The local structure and interactions in the cyclopentanone intercalate have been suggested on the basis of quantum chemical calculations. r 2004 Elsevier Inc. All rights reserved. Keywords: Intercalation; Vanadyl phosphate; Powder X-ray diffraction; Vibrational spectroscopy; Ab initio calculation 1. Introduction Vanadyl phosphate dihydrate VOPO 4  2H 2 O and other isostructural layered compounds are able to accommodate some types of organic molecules in the interlayer space [1]. Aliphatic alcohols and diols [2–4], amines [5], carboxylic acids [6], carboxamides [7], aliphatic nitriles [8] belong to the compounds, which can be intercalated in such a way. Great attention was devoted to the intercalation of heterocyclic N- and S- donors [9–13]. Recently, intercalation of ketones [14,15], aldehydes [16], poly(ethylene glycol)s [17,18], hetero- cycles with O-donor [18–20], and g-butyrolactone [21] into vanadyl phosphate has been described. These guests are anchored to the host layers by donor–acceptor bonds of their carbonyl or etheric oxygen to the vanadium atoms. These intercalates, except aliphatic aldehyde intercalates, are generally very stable in air and the guest molecules are released at relatively high temperatures (for example tetrahydrofuran intercalate decomposes at about 160 1C [19]). It indicates that the host–guest interaction is very strong. Some of these intercalates are well crystalline solids and their diffrac- tograms show, besides a series of sharp (00l) reflections, a number of (hkl) diffraction lines giving evidence of a regular structure. The present paper reports the results of the intercala- tion of cyclopentanone, cyclohexanone, 4-methylcyclo- hexanone, and 1,4-cyclohexanedione into vanadyl phosphate. 2. Experimental The propanol or ethanol intercalates were prepared by suspending microcrystalline VOPO 4  2H 2 O in dry propanol or ethanol and subsequent short exposure to a microwave field. The intercalation compounds were obtained by displacing propanol or ethanol in VOPO 4  2ROH with the corresponding guest. The cyclopenta- none intercalate was prepared by stirring the propanol intercalate (0.5g) with cyclopentanone (20mL) at room temperature overnight. The cyclohexanone and ARTICLE IN PRESS www.elsevier.com/locate/jssc 0022-4596/$-see front matter r 2004 Elsevier Inc. All rights reserved. doi:10.1016/j.jssc.2004.11.008 Ã Corresponding author. Fax: +420466036151. E-mail address: vitezslav.zima@upce.cz (V. Zima).