Page 1 of 8 Dalton Transactions

Dalton Transactions Accepted Manuscript This is an Accepted Manuscript, which has been through the Royal Society of Chemistry peer review process and has been accepted for publication. Accepted Manuscripts are published online shortly after acceptance, before technical editing, formatting and proof reading. Using this free service, authors can make their results available to the community, in citable form, before we publish the edited article. We will replace this Accepted Manuscript with the edited and formatted Advance Article as soon as it is available. You can find more information about Accepted Manuscripts in the Information for Authors. Please note that technical editing may introduce minor changes to the text and/or graphics, which may alter content. The journal’s standard Terms & Conditions and the Ethical guidelines still apply. In no event shall the Royal Society of Chemistry be held responsible for any errors or omissions in this Accepted Manuscript or any consequences arising from the use of any information it contains. www.rsc.org/dalton Page 1 of 8 Dalton Transactions Manuscript Accepted Two novel arsenic(III) oxide intercalates with potassium and ammonium azides have been synthesized and their crystal structures have been determined. Transactions Dalton Journal Name Dalton Transactions Dynamic Article LinksPage ► 2 of 8 Cite this: DOI: 10.1039/c0xx00000x www.rsc.org/xxxxxx ARTICLE TYPE Structure and energetics of arsenic(III) oxide intercalated by ionic azides Piotr A. Guńka,*a Karol Kraszewski,a Yu-Sheng Chenb and Janusz Zacharaa Received (in XXX, XXX) Xth XXXXXXXXX 20XX, Accepted Xth XXXXXXXXX 20XX 5 DOI: 10.1039/b000000x Unprecedented intercalates of arsenic(III) oxide with potassium azide and ammonium azide have been obtained and characterized by single crystal X-ray diffraction. The compounds are built of As2O3 sheets separated by charged layers of cations and azide anions perpendicular to the sheets. The intercalates are an interesting example of hybrid materials whose structure is governed by covalent bonds in two 10 directions and ionic bond in the third one. Obtained compounds are the first example of As2O3 intercalates containing linear pseudohalogen anions. Periodic DFT calculations of interlayer interaction Manuscript energies were carried out with the B3LYP-D* functional. The layers are held together mainly by ionic bond, although the computations indicate that interactions between cations and As2O3 sheets also play a significant role. Comparison of cation and anion interaction energies with neutral As2O3 sheets sheds light 15 on crystallisation process, indicating the templating effect of potassium and ammonium cations. It consists in the formation of sandwich complexes of cations with crown-ether-resembling As6O12 rings. Raman spectra of both compounds are recorded and computed ab initio and all vibrational bands are assigned. Introduction Accepted Experimental and computational details 20 Intercalation compounds result from inclusion, without covalent bonding, of molecules or ions in a solid matrix of another All chemicals used, except for NH4AsO2 which was synthesized 1 13 compound which has a layered structure. Intercalates of various 50 as described previously, were obtained from commercial inorganic hosts exhibit a wide range of interesting properties and sources and were used as received, without further purification. find numerous every-day applications. Lithium intercalates of Reactions were carried out in open glass vessels. 25 transition-metal-based materials such as LiMnO2, LiCoO2 and NH4N3∙2As2O3 (1). NH4AsO2 crystals were stored at 5°C after 2,3 FePO4 are utilised as electrodes in lithium-ion batteries, the synthesis in a closed vessel in a saturated aqueous solution of whereas iron arsenide and iron selenide based intercalates with 55 ammonium arsenite. 75 mg of the crystals were taken together metals or with metals and organic solvents can be with 0.5 mL of the solution and were mixed with a solution of 98 4–8 superconducting at temperatures as high as ~50 K. The alkali mg of NaN3 in 3 mL of water. The mixture was stirred until all 30 metals intercalates of graphite are used as reducing agents in ammonium arsenite was dissolved and the resulting solution was 9 chemical synthesis. There is a number of arsenic(III) oxide left for crystallisation via slow water evaporation. When a third Transactions intercalates described in the literature whose crystal structures 60 of the initial solution volume was left in the vessel, crystallisation have been determined. These include hexagonal KX∙2As2O3 was stopped yielding single crystals of compound 1 exclusively 10 where X=Cl, Br, I; NH4Y∙2As2O3 where Y=Br, I; hydrated with a yield of 60%. 11 12 35 2NH4Cl∙4As2O3∙H2O and orthorhombic NaBr∙2As2O3. To the KN3∙2As2O3 (2). 0.4 g of As2O3 powder (2 mmol) was added to 3 best of our knowledge, there are no publications reporting ml of 2M KOH solution (6 mmol) and stirred until all As2O3 was intercalates with other types of ions, particularly non-spherical 65 dissolved. Afterwards, 0.13 g of NaN3 (2 mmol) was dissolved in ones. We have, therefore, attempted to synthesise arsenic(III) the solution. Then, concentrated HNO3 solution was added Dalton oxide intercalates with salts containing ions with different dropwise until a solid phase precipitated (pH ~ 9-10 was achieved 40 geometry and, herein, we report the synthesis and crystal at this point). The resulting powder was filtered and washed with structures of the first As2O3 intercalates containing linear a mixture of methanol and concentrated HNO3 (9:1, V/V) twice. pseudohalogen anions. In order to understand the contribution of 70 The powder was dried on filter paper. Such a procedure leads to various components to the interlayer interaction energies, we pure intercalate 2 with a yield of 65%. In order to grow single have performed periodic DFT computations with the B3LYP-D* crystal suitable for X-ray diffraction experiment, the solution was 45 functional. Moreover, we show experimental Raman spectra of diluted five times before the addition of HNO3. Nonetheless, all the intercalates with all the bands assigned by comparison with attempts led to tiny, plate-shaped single crystals whose theoretical vibrational frequencies. 75 diffraction pattern was only measurable using synchrotron X-ray This journal is © The Royal Society of Chemistry [year] [journal], [year], [vol], 00–00 | 1 Page 3 ofJournal 8 Name Dalton Transactions Dynamic Article Links ► Cite this: DOI: 10.1039/c0xx00000x www.rsc.org/xxxxxx ARTICLE TYPE Manuscript Accepted Fig. 1 Crystal structures of intercalates 1 and 2. View along the [001] direction in a ball and stick model and view along the [120] direction with ADPs visualised are presented at the top and at the bottom, respectively. Thermal ellipsoids are drawn at the 50% probability level. Transactions source. K. Data reduction and analysis including multi-scan absorption 5 Suitable single crystals were selected under a polarizing and oblique corrections were carried out using the APEX-II suite 16 microscope, mounted in inert oil and transferred to the cold gas 20 and SADABS. The structures were solved by direct methods stream of the diffractometer. Diffraction data for compound 1 and subsequent Fourier-difference synthesis and refined by full- were measured at RT with graphite-monochromated Mo-Kα matrix least-squares against F2 with SHELX-201317 within the radiation on the Oxford Diffraction κ-CCD Gemini A Ultra Olex2 suite which was also used for data analysis.18 Ammonium Dalton 14 10 diffractometer. Absorption effects were corrected analytically. cations in compound 1 lie on a special position exhibiting 6/mmm Cell refinement and data collection as well as data reduction and 25 site symmetry and, hydrogen atoms, are disordered. Figures of analysis were performed with the Oxford Diffraction software crystal structures were created using Diamond19 and rendered CrysAlisPRO.15 Diffraction data for compound 2 were collected at with POV−Ray.20 All of the discussions on crystal structure of ChemMatCARS beamline, 15-ID-B, at the Advanced Photon compound 2 relate to the 45 K measurement, if not stated ‡ 15 Source (APS), U.S.A. A Bruker APEXII CCD detector was used otherwise. to record the diffracted intensities at λ = 0.38745 Å (32 keV) and 30 Raman spectra were recorded using Nicolet Almega Dispersive at the following temperatures 45(2), 35(2), 25(2), 15(2) and 30(2) Raman spectrometer. Spectra of powders of 1 and 2 were This journal is © The Royal Society of Chemistry [year] [journal], [year], [vol], 00–00 | 2 Dalton Transactions Page 4 of 8 obtained using 780 nm excitation line and a 1200 lines/mm and 3.189(5) for 2 which is a little less than sum of arsenic and resolution grating. The exposition time was 30 s. nitrogen van der Waals radii (3.40 Å), indicating the presence of Periodic quantum mechanical computations were carried out weak interactions between arsenic atoms and azide anions. 21–23 using the CRYSTAL09 programme suite. Calculations were 60 Similarly as in intercalates with potassium and ammonium 24,25 5 performed within the DFT framework using the hybrid halides, the threefold coordination of arsenic atoms by oxygen 26 − B3LYP functional with an all-electron TZVP basis set ligands is complemented by three N3 anions, forming a distorted 27 − optimised for solid state computations (pob-TZVP). Dispersion octahedron. A survey of CSD reveals that As∙∙∙N3 contacts interactions were accounted for by an empirical correction

Load more