The Preparation and Properties of Some Fluorometallates
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University of New Hampshire University of New Hampshire Scholars' Repository Doctoral Dissertations Student Scholarship Fall 1960 THE PREPARATION AND PROPERTIES OF SOME FLUOROMETALLATES DAVID SCOTT CROCKETT III. University of New Hampshire, Durham Follow this and additional works at: https://scholars.unh.edu/dissertation Recommended Citation CROCKETT, DAVID SCOTT III., "THE PREPARATION AND PROPERTIES OF SOME FLUOROMETALLATES" (1960). Doctoral Dissertations. 2356. https://scholars.unh.edu/dissertation/2356 This Dissertation is brought to you for free and open access by the Student Scholarship at University of New Hampshire Scholars' Repository. It has been accepted for inclusion in Doctoral Dissertations by an authorized administrator of University of New Hampshire Scholars' Repository. For more information, please contact [email protected]. THE PREPARATION AND PROPERTIES OF SOME FLUOROMETALLATES BY DAVID SCOTT CROCKET III A. B. Colby College, 1952 M. S. University of New Hampshire, 195^ A THESIS Submitted to the University of New Hampshire In Partial Fulfillment of The Requirements for the Degree of Doctor of Philosophy Graduate School Department of Chemistry August, 1959 This thesis has been examined and approved D ate Acknowledgement This work was carried, out in the James Hall Chemical Laboratories of the University of New Hampshire under the direction of Dr, Helmut M. Haendler. It was sponsored in part by the Atomic Energy Commission. Appreciation is also extended to the International Business Machines Corporation and to the Massachusetts Institute of Technology for use of the I.B.M. 70l\. Computer. It has been a very pleasant and enlightening experi ence to work under the guidance of Dr. Haendler. The author tin >ks him for the freely given time and effort he has expended in the author* s behalf. Thanks are also due to the other members of the Chemistry faculty and staff. i Table of Contents Page Acknowledgement 1 List of Tables 111 List of Figures v INTRODUCTION 1 CHAPTER I k The Preparation of Ammonium Fluorometallate Complexes In Methanol k. The Preparation of Diammonium Tetrafluoro- cuprate (II) 7 CHAPTER II 8 The Fluorome ta ll ate s of Potassium, Rubidium and Cesium 8 CHAPTER III 17 The Structural Studies of Some Fluorometallate Complexes 17 APPENDIX k Z Calculation of Interplanar Spaclngs on the I.B.M. 70i|. l\Z Halocarbon oil as a mulling medium for Infrared Spectra lj - 6 Tables of Data k 7 Bibliography 6 6 11 List of Tables Page I Potassium Fluorometallates 9 II Rubidium Fluorometallates 10 III Cesium Fluorometallates 11 IV Comparison of Interplanar Spacings from x-ray Powder Photographs 20 V Infrared Speotra 28 VI Unit Cell Parameter, "a” 35 VII Potassium Trifluorocuprate II 39 VIII I.B.M. 701). Programs 1|4 IX I.B.M. 704 Programs X Ammonium Trifluorocobaltate II 47 XI Potassium Trifluorocobaltate II lj . 8 XII Rubidium Trifluorocobaltate II 49 XIII Ammonium Trlfluoromanganate II 50 XIV Potassium Trlfluoromanganate II 51 XV Rubidium Trlfluoromanganate II 52 XVI Ammonium Trifluorozincate II 53 XVII Potassium Trifluorozincate II 54 XVIII Rubidium Trifluorozincate II 55 XIX Diammonium Tetrafluoronickelate II $ 6 XX Ammonium Trifluorocuprate II 57 XXI Potassium Trifluorocuprate II 58 XXII Rubidium Trifluorocuprate II 59 XXIII Dlammonlum Tetrafluorocuprate II 6 o XXIV Dipotassium Hexafluorozirconate IV 6 l i i i List of Tables (cont.) P a g e XXV D ic e slum Hexafluoroziroonate IV 62 XXVI Ammonium Trlfluorocadmate II 6 3 XXVII Potassium Trlfluorocadmate II 61). XXVIII Rubidium Trifluoroeadmate II 65 List of Figures Page I Infrared Spectra of KCuOHFg and CuOHF 2 2 II The Thermal Decomposition of (NHj^) 2k III Conqparison of Powder Patterns of the Thermal Decomposition Products of (NHj^NiF^ 2$ IV The Infrared Spectrum of (NH^JgNiF^ 31 V The Infrared Spectrum of (NHj^gOQF^ 32 VI A Comparison of the powder Patterns of NHjjMiF^i NH^CoF^, KCoF^ and KMaF^ 3 k VII A Comparison of the Powder Patterns of NH^CuF^, KCuF^ and RbCuF^ 38 v INTRODUCTION Although there has been a trend In recent years toward the use of non-aqueous media in the field of inorganic chem istry, anhydrous methanol has been very rarely used as a sol vent. This is due in part to the comparatively low solubilities of many inorganic compounds in methanol as compared to water. The use of methanol as a solvent has a distinct advantage over many of the more common non-aqueous media such as fused systems, liquid ammonia, liquid hydrogen fluoride, or liquid sulfur dioxide, in that it can be handled without special equipment or elaborate precautions. Of the common organic solvents, methanol is probably the most water-like, with many salts displaying electrolytic behavior. Thus come of the advantages of an aqueous system have been retained while the possibility of hydration and hydrolysis has been very largely eliminated. In an earlier work‘d the author reported the formation of ammonium fluorometallate complexes prepared in methanol by the reaction of ammonium fluoride with the halides of zinc and cadmium. The reaction can be represented by the equation 3NH|jF + MsBr2 NH^MeP^I + 2NH^Br. O Subsequently Johnson*- developed a method for the preparation of metal bromides in methanol and prepared an additional number of ammonium fluorometallates. These are Included in the reprint in Chapter I of this thesis, with the ammonium complexes prepared as part of the present work. 1 a Since the solubility of potassium, rubidium, and. cesium fluorides in methanol compares favorably with that of ammonium fluoride, the reaction with metal bromides in methanol was extended to Include these alkali fluorides as well* Chap ter II deals with the preparation and properties of these com plexes* Of the conplex fluorides, the potassium fluorom etallates are perhaps the best known* This is due in part to the avail ability of potassium fluoride, as compared to rubidium and cesium fluoride, and to the fact that the complexes can be prepared from m elts, and in certain instances in aqueous so lutions. Certain potassium fluorometallate complexes, of the type KMeF^, have aroused considerable interest, since they are of the perovsklte structure, and exhibit anti-ferromag- etism* The recent determination of the structure of some of these complexes^ has ended considerable controversy concerning their structures. In Chapter III some structural properties of the fluorometallate complexes are considered. From the x-ray powder photographs It has been possible to relate the structures of the ammonium and rubidium complexes to the known structures of the potassium complexes, and in some instances to show their isomorphism. X-ray powder patterns have also made it possible to show the structures of the complexes, as prepared in methanol, to be identical to that of the same compound prepared by other means. The thermal decomposition o f some o f th e ammonium f lu o r o m e t a lla t e s h a s b e e n s t u d ie d and the resulting products identified by means of analysis or x-ray powder patterns. Infrared spectra have also been 3 utilized in the study of certain ammonium complexes and the spectra have been related to the structural characteristics of the compounds. In the appendix is Included a description of some computer programs for the calculation of interplanar spaclngs from the cell constants of the various crystal systems. These were written for use with the I.B.M. 70i|. computer at the Massachusetts Institute of Technology, and have been use ful in the Interpretation of x-ray data. Also included in the appendix is a published note concerning the use of Halo- carbon oil as a mulling agent. This was developed in connec tion with the infrared work on the ammonium fluorometallates. CHAPTER I [Reprinted from the Journal of the American Chemical Society, 80, 2062 (1958).] Copyright 1968 by the American Chemical Society and reprinted by permission of the copyright owner. [C ontribution pr o m t h e D b p a r t m b n t o p C h e m is t r y , U n iv e r s it y o f N e w H a m p s h ir e ] The Synthesis of Ammonium Fluorometallates in Methanol1* B y H e l m u t M. H aendler, Frederic A. J o h n s o n 16 and David S. C r o c k e t Received December 0, 1957 A series of seventeen anhydrous ammonium fluorometallates has been prepared by reaction of methanol solutions of the metal bromides and ammonium fluoride. The products have been identified by X-ray and chemical analysis. Introduction Experimental The chemistry of reactions of simple inorganic Preparation of the Metal Bromides.—In each case the compounds in organic solvents has been somewhat bromide was prepared by action of bromine on finely divided metal suspended in methanol. Excess bromine was used, neglected, attention having been concentrated on except in the preparation of the iron(II) complex. The organic systems containing water as one compo bromine was added in 1-ml. portions from a dropping nent. Comparisons of solubilities suggested to us funnel to a stirred suspension of 0.1 mole of metal in approxi the possibility of preparing anhydrous fluorides by mately 100 ml. of cooled "Absolute” methanol. The resultant solution was filtered to remove any insoluble metathesis in methanol, using ammonium fluoride residue and diluted to an approximately known molarity in a and a metal halide. It was found, however, that volumetric flask. The method is similar to that of Osthoff in most cases an ammonium fluorometallate was and West* and of Ducelliez and Raynaud.* produced. Preparation of the Complexes.—In all cases the reaction A m m onium was carried out by the addition of metal bromide solution fluorometallates have long been of to a rapidly stirred saturated solution of ammonium fluoride interest because of the structural problems they in a polyethylene container.