A solid-state study of tervalent hexachloro-complexes R3MCl6(M= Rh or Ir) and quadrivalent hexachlorocomplexes R2MCl6(M= Mn, Tc, Ru, and Rh) has been carried out by use of X-ray, n.q.r., and i.r. techniques. The 35Cl n.q.r. spectra of the complexes K3RhCl6,H2O, K3lrCl6,H2O, K3lrCl6, and (NH4)3lrCl6,H2O are complex and suggest a low site-symmetry for the anion. This is verified from the low-frequency i.r. spectra of the compounds and a full single-crystal X-ray analysis of K3RhCl6,H2O. The latter complex is orthorhombic and has space-group Pbcn with 8 molecules Z= 8 in a unit cell of dimensions a= 1·2368(9), b= 1·5655(6), and c= 1·2041 (10) nm. The structure was solved from diffractometer data and refined R 0·07 for 920 independent reflexions. The octahedral RhCl63– anions contain six crystallographically independent Rh–Cl bonds ranging in length from 230·2(4) to 236·6(4) pm. The lack of symmetry in the anion appears to be influenced by the neighbouring molecule of water of crystallisation. The n.q.r. spectra of the cubic octahedral quadrivalent complexes R2MCl6(M= Mn, Tc, Ru, or Rh) have been measured and display the same trends as observed previously for the metal hexachloro-complexes of the third transition-series.

Chemischer InformationsdienstVolume 3, Issue 17 Preparative Inorganic Chemistry ChemInform Abstract: HEXACHLOROMETALLATE (I-II), INFRAROT- UND KERNQUADRUPOLRESONANZSPEKTREN SOWIE ROENTGEN-STRUKTURUNTERSUCHUNGEN P. J. CRESSWELL, P. J. CRESSWELLSearch for more papers by this authorJ. E. FERGUSSON, J. E. FERGUSSONSearch for more papers by this authorB. R. PENFOLD, B. R. PENFOLDSearch for more papers by this authorD. E. SCAIFE, D. E. SCAIFESearch for more papers by this author P. J. CRESSWELL, P. J. CRESSWELLSearch for more papers by this authorJ. E. FERGUSSON, J. E. FERGUSSONSearch for more papers by this authorB. R. PENFOLD, B. R. PENFOLDSearch for more papers by this authorD. E. SCAIFE, D. E. SCAIFESearch for more papers by this author First published: April 25, 1972 https://doi.org/10.1002/chin.197217008AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume3, Issue17April 25, 1972 RelatedInformation

J.E. Fergusson and D.E. Scaife (Received 14 June 1971) Several papers (1,2,3,4,5,6) have dealt with the temperature dependence of chlorine N.Q.R. frequencies in isostructural cubic compounds A2MCI6, where M is a metal of the third row transition series. Some results are also available for Cs2MoCI 6 (4) and K2PdCI 6 (7). We report here data for some other members of the second row series. The detailed data for K2TcCI 6 and K2RuCI 6 are shown in Figure 1.

Chlorine nuclear quadrupole resonance frequencies are reported for solid compounds of known structure containing linear molecules HgCl2 and Hg2Cl2, approximately trigonal HgCl3-, and a variety of distorted octahedral forms including NH4HgCl3, CsHgCl3, and K2HgCl4,H2O. Compounds of unknown structure of the type (cation+)HgCl3, (cation+)2HgCl4, (cation+)Hg2Cl5, (cation+)2Hg9Cl20, and (cation+)4HgCl6 have also been studied. There are clear correlations between observed n.q.r. frequencies and Hg-Cl infrared stretching frequencies and bond distances. These correlations show the dependence of the degree of covalent bonding in the Hg-Cl bond with distance. The n.q.r. data confirm that many of the complex chlorides of mercury are built up by the joining of octahedral HgCl6 units, distorted in such a way as to preserve to varying extents the identity of the HgCl2 molecule. Predictions of the structures are made for some complex chlorides of unknown structure, and the role of bridging in building up the compounds is discussed in terms of observed n.q.r. data for bridging chlorines.

Compounds of the type (cation+)MCl4- form isomorphous series when (cation+) = Ph4P+ and Ph4As+, and M = Al, Ga, In, Tl, V, and Fe in their trivalent states. X-ray data, infrared data, and for the vanadium compounds, magnetic and electronic spectral data, also suggest that the series is isomorphous, with the MCl4- ion having a slightly distorted tetrahedral symmetry. 35Cl nuclear quadrupole resonance results for the Al and Tl compounds indicate a site symmetry of S4 for the MCl4- ion. Magnetic data for the vanadium compounds, and also for (Bun)4NVCl4, show some antiferromagnetic interaction of the VCl4- ions in these lattices. Infrared data are also presented for (Ph4As)2InCl5, Ph4PSbCl4, Ph4AsSbCl4, Ph4PBiCl4, and PhdAsTiCl4, none of which appears to contain tetrahedral MCl4- ions.

Anhydrous vanadium trichloride and tribromide react with acetonitrile to produce non-electrolytic complexes of the type [VX3,3CH3CN](X = Cl or Br) both in solution and in the solid state. Addition of tetraethylammonium, methyltriphenylarsonium, or tetraphenylarsonium chlorides to acetonitrile solutions of the above result in the precipitation of complexes of the type R+[VX4,2CH3CN]–(R = Et4N+, MePh3As+, or Ph4As+). Mixed halogeno-species of this type may also be synthesised. Reaction of the complex Et4N[VCl4,2CH3CN] with dry pyridine or with 2,2′-bipyridyl or 1,10-phenanthroline (in acetonitrile) yields complexes of the type Et4N[VCl4,2L], where L = py, ½ bipy, or ½ phen. Studies of the visible and infrared spectra of all the above complexes demonstrate that in each case the vanadium(III) is octahedrally co-ordinated, and estimates of the ligand-field splitting parameter (Dq) and Racah parameter (B) for these complexes are given.Thermal decomposition of the bis-acetonitrile derivatives at 100° yield complexes of the type R+VX4–(X = Cl or Br) as well as the mixed complex Et4N+ VCl3Br–. The electronic spectra (band positions and extinction coefficients), infrared spectra, and X-ray powder photographs of the complexes demonstrate conclusively that the VX4– ions are tetrahedral in the salts Ph4AsVCl4, Ph3MeAsVCl4, and Et4NVBr4, as might be expected for four-co-ordinate ions with the e2 configuration. The parameter 10Dq is calculated to be 5400 cm.–1 for the VCl4– ion. The room-temperature magnetic moments of the complexes (∼2·8 B.M.) are consistent with the presence of two unpaired electrons per vanadium atom in each case.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTDimorphism in Thorium TetrabromideD. E. ScaifeCite this: Inorg. Chem. 1966, 5, 1, 162–164Publication Date (Print):January 1, 1966Publication History Published online1 May 2002Published inissue 1 January 1966https://doi.org/10.1021/ic50035a044RIGHTS & PERMISSIONSArticle Views43Altmetric-Citations12LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (359 KB) Get e-Alerts Get e-Alerts

A cell is described with which the reflectance spectra of air-sensitive powders can be measured from room temperature down to liquid nitrogen temperature.

D. E. Scaife, A. G. Turnbull and A. W. Wylie, J. Chem. Soc., 1965, 1432 DOI: 10.1039/JR9650001432

An air-tight sample holder is described which enables a Hagg Guinier-type camera to be used to obtain x-ray powder photographs of air-sensitive materials.

D. E. Scaife and A. W. Wylie, J. Chem. Soc., 1964, 5450 DOI: 10.1039/JR9640005450

A simple technique has been developed for obtaining reflection spectra from solids and the near infra-red combination spectra of a number of cyclopentadienyl compounds have been recorded. The method makes possible the spectral identification of the cyclopentadienyl ring structure in reactive solid compounds and complements proton magnetic resonance and infra-red transmission spectra characterizations. The combination spectra above 3800 cm−1 are similar and characteristic of a C5H5 ring bonded with five-fold symmetry to a metal atom, and with, as a particular feature, a single sharp CH stretching overtone at 6100–6200 cm−1. The spectra of the solids are compared with near infra-red solution spectra obtained for ferrocene and C5H5TiCl3; the combination spectrum of ferrocene is assigned from its known fundamentals.

The main qualitative differences between the spectra of pyridine, co-ordinated pyridine and the pyridine ion are discussed and an assignment is made for all the bands observed in the spectra of co-ordinated pyridine. In view of the small shifts observed when comparing the spectra of pyridine complexes, it is concluded that the electron density over the pyridine ring remains almost constant whatever the acceptor atom and it is suggested that back-bonding plays a part in the bonding of these complexes. some of the N-H bands in the spectra of the pyridinium ion have been identified by deuteration and the spectra of this ions are discussed.

Thorium carbide can be used as a feed material for production of thorium metal filaments by a Van Arkel-de Boer-type process. Factors influencing the synthesis of carbide from oxide and the growth of thorium metal from carbide were studied and optimum conditions of growth established. Metal having a carbon, nitrogen, and oxygen content lower than the best material obtainable from a conventional metal feed can be produced at satisfactory rates and temperatures. A thorium iodide decomposition unit with carbide feed material involves processes which are highly efficient at separating from thorium ail major metallic impurities except zirconium, hafnium, and uranium. A large group of these impurities is volatilized at the high temperatures needed for carbide formation. The residual impurities are then eliminated by one or other of the several exclusion processes operating in the iodide formation and decomposition bulb. Application of the process to larger-scale operation is briefly discussed. Finally, attention is drawn to the excellent decontamination from fission products possible with irradiated thorium materials. (auth)