THE FLUORIDES OF PLATINUM and related compounds by DEREK HARRY LOHMANN B.Sc, University of London, 1953 M.Sc, Queen's University, Ontario, 1959 A THESIS SUBMITTED IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY in the Department of CHEMISTRY We accept this thesis as conforming to the required standard. THE UNIVERSITY OF BRITISH COLUMBIA October 1961, In presenting this thesis in partial fulfilment of the requirements for an advanced degree at the University of British Columbia, I agree that the Library shall make it freely available for reference and study. I further agree that- permission for extensive copying of this thesis for scholarly purposes may be granted by the Head of my Department or by his representatives. It is understood that copying or publication of this thesis for financial gain shall not be allowed without my written permission. Department of CHEMISTRY The University of British Columbia, Vancouver 8, Canada. Date 31st October 1961. %\\t Pntesttg of ^irtttslj Columbia FACULTY OF GRADUATE STUDIES PROGRAMME OF THE FINAL ORAL EXAMINATION FOR THE DEGREE OF DOCTOR OF PHILOSOPHY PUBLICATIONS oi . I. "Polar effects in Hydrogen abstraction reactions," M. P. Godsay, DEREK HARRY LOHMANN D. H. Lohmann and K. E. Russell, Chem. and Ind., 1959, 1603. B.Sc, University of London, 1953 M.Sc, Queen's University, Ontario, 1959 2. "Two new fluorides of Platinum," N. Bartlett and D. H. Lohmann, Proc. Chem. Soc, 1960, 14. TUESDAY, NOVEMBER 28th, 1961, AT 1:00 P.M. 3. "The reaction of 2,2-Diphenyl-l-Picrylhydrazyl with 9,10-Dihy- droanthracene and 1,4-Dihydronaphthalene," I. S. Hogg, D. H. IN ROOM 342, CHEMISTRY BUILDING Lohmann and K. E. Russell, Canad. J. Chem., 1961, 39, 1394. 4. "The kinetics of reaction of 2,2-Diphenyl-l-Picrylhydrazyl with COMMITTEE IN CHARGE phenols," I. S. Hogg, D. H. Lohmann and K. E. Russell, Canad. Chairman: F. H. SOWARD J. Chem. 1961, 39, 1588. N. BARTLETT C. A. McDOWELL K. B. HARVEY V. J. OKULITCH L. D. HAYWARD E. TEGHTSOONIAN External Examiner: H. J. EMELEUS Cambridge University THE FLUORIDES OF PLATINUM AND RELATED The crystal structures of the tetrafluorides of platinum rhodium, COMPOUNDS tin and lead were investigated. No similarity in structure was found. A brief investigation into the fluorides of rhodium has led to ABSTRACT the suggestion that a pentafluoride, in addition to a terafluoride, The fluorides of platinum have been reinvestigated. Attempts exists. to prepare a difluoride were unsuccessful. It is suggested that this is due to it being unstable towards disproportionation. X-ray Crystallographic evidence is presented as evidence for a trifluoride of platinum although a pure sample has not been isolated. GRADUATE STUDY This trifluoride is shown to be isostructural with the rhombo- hedral trifluorides of palladium, iridium and rhodium. Field of Study: Chemistry Platinum tetrafluoride has been reinvestigated. It was found to be diamagnetic and to have a lattice of slightly-distorted, tetra• Topics in Inorganic Chemistry N. Bartlett, H. C. Clark, gonal uranium tetrachloride type. The adducts of platinum tetra• fluoride with bromine trifluoride and selenium tetrafluoride were W. R. Cullen, G. J. Willis investigated further and found to be diamagnetic. The platinum tetrafluoride, selenium tetrafluoride adduct was shown to be iso• Advanced Inorganic Chemistry N. Bartlett, H. C. Clark structural with the corresponding palladium and germanium com• pounds. An ionic lattice is suggested for these compounds. Bromine Crystal Structures K. B. Harvey, L. W. Reeves trifluoride adducts do not form a similar series and this, combined with their physical properties, led to the suggestion that these com• Molecular Structure L. W. Reeves, C. Reid, J. Trotter pounds are more covalent in nature. Seminar in Chemistry N. Bartlett, K. B. Harvey The previously unknown pentapositive state of platinum has bein established. Platinum pentafluoride is a deep-red, reactive Other Studies: solid which readily disproportionates on heating. It gives rise to 1:1 adducts with iodine pentafluoride and chlorine trifluoride. These, Differential Equations C. Froese like the bromine trifluoride adducts, are low-melting solids. Potas• sium fluoroplatinate (V) was prepared as a deep-yellow solid, Digital Computers H. Dempster crystallizing with the rhombohedral potassium fluorosmate lattice. A pentapositive oxyfluoride, platinum oxytrifluoride, was found; it Nuclear Physics J. B. Warren is suggested that this is polymeric. Platinum hexafluoride has been briefly investigated. A very reactive oxyfluoride, of formula PtO„F6, has been pre• pared and investigated. It is a deep-red solid which can be sublimed at 90° in a vacuum. It melts with decomposition at 219°. It is paramagnetic and crystallizes in a cubic lattice. Many of its chemi• cal properties were studied. It is suggested that this compound is platinum peroxidehexafluoride. ,1 British Columbia * REQUEST * Transaction Number 4642692 Patmn Name PaLrM. Number Item Number 39424050651303 Lille Fluorides of platinum and related coi Pickup Location I.K. BARBER circulat Qgto/Ti mp (ii) ABSTRACT The fluorides of platinum have been.reinvestigated. Attempts to prepare a difluoride were unsuccessful. It is suggested that this is- due to it being unstable towards disproportionation. X-ray Crystallographic evidence is presented as evidence for a trifluoride of platinum although a pure sample has not been, isolated. This trifluoride is shown to be isostructural with the rhombohedital trifluorides of palladium, iridiumi and rhodium. Platinum tetrafluoride has been reinvestigated. It was found to be diamagnetic and to have a lattice of slightly-distorted, tetragonal uranium tetrachloride type. The adducts of platinum tetrafluoride with bromine trifluoride and selenium tetrafluoride were investigated further and found to be diamagnetic. The platinum tetrafluoride, seleniumi tetra• fluoride adduct was shown* to be isostructural with the corresponding palladium and germanium compounds. An ionic lattice is suggested for these compounds. Bromine trifluoride adducts do not form a similar- series and this, combined with their- physical properties lead to the suggestion that these compounds are more covalent in nature. The previously unknown pentapositive state of platinum has been established. Platinum pentafluoride is a deep-red, reactive solid which readily disproportionates on heating. It gives rise to 1:1 adducts with iodine pentafluoride and chlorine trifluoride. These, like the bromine trifluoride adducts, are low-melting solids. Potassium fluoroplatinate (v) was prepared as a deep-yellow solid, crystallizing with the rhombohedral potassium fluorosmate lattice. A pentapositive oxyfluoride, platinum oxytrifluoride was found, it is suggested that this is polymeric. Platinum hexafluoride has been briefly investigated. (iii) A very reactive oxyfluoride, of formula PtO^Fg, has been prepared and investigated. It is a deep-red solid which can be sublimed at 90° in a vacuum. It melts with decomposition! at 219°. It is para• magnetic and crystallizes in a cubic lattice. Many of its chemical properties were studied. It is suggested that this compound is platinum peroxidehexafluoride. The crystal structures of the tetrafluorides of platinum rhodium, tin and lead were investigated. No similarity in structure was found. A brief investigation into the fluorides of rhodium has lead to; the suggestion! that a pentafluoride, in addition to a tetrafluoride, exists. (iv) TABLE OF CONTENTS Page ABSTRACT ii TABLE OF CONTENTS iv LIST OF TABLES vi LIST OF FIGURES vii LIST OF PLATES vii ACKNOWLEDGEMENTS viii INTRODUCTION 1 EXPERIMENTAL ANALYSIS 11 PHYSICAL METHODS 18 MATERIALS 20 APPARATUS FOR HANDLING FLUORINE 25; FLUORINATION REACTIONS 26 PLATINUM DIFLUORIDE 30 PLATINUM TRIFLUORIDE 31 PLATINUM TETRAFLUORIDE 32 THE PLATINUM TETRAFLUORIDE, BROMINE TRIFLUORIDE ADDUCT . 39 THE PLATINUM TETRAFLUORIDE, SELENIUM TETRAFLUORIDE ADDUCT 39 PLATINUM PENTAFLUORIDE 44 POTASSIUM FLUOROPLATINATE (V) 46 THE PLATINUM PENTAFLUORIDE, IODINE PENTAFLUORIDE ADDUCT. 50 THE PLATINUM PENTAFLUORIDE, CHLORINE TRIFLUORIDE ADDUCT. 50 PLATINUM OXYTRIFLUORIDE 52 PLATINUM HEXAFLUORIDE 53 PtO„Fc PLATINUM PEROXIDEHEXAFLUORIDE? 2 o Preparation, 53 Purification 55 Properties 56 Crystal Structure 5:7 Mass spectrum 59 Infra—red spectrum. ............ 59 Ultra violet and visible spectrumi 60 Magnetic study 60 Vapour pressure study ......... 61 Reactions 61 RHODIUM TETRAFLUORIDE 66 RHODIUM PENTAFLUORIDE? 69 POTASSIUM FLUORORHODATE (V) 70 TIN TETRAFLUORIDE 72 LEAD TETRAFLUORIDE 75. Page DISCUSSION THE VALENCY STATES OF PLATINUM 7.6 PLATINUM DI FLUORIDE 79 PLATINUM TRIFLUORIDE 82 PLATINUM TETRAFLUORIDE . 84 PLATINUM PENTAFLUORIDE 87 POTASSIUM HEXAFLUOROPLATINATE (V) 90 PLATINUM OXYTRIFLUORIDE 92 PLATINUM HEXAFLUORIDE 93 PtO F PLATINUM PEROXIDEHEXAFLUORIDE? 94 THE COMPLEXES OF QUADRIPOSITIVE PLATINUM 100 THE TETRAFLUORIDES 103 THE FLUORIDES OF PALLADIUM 106 THE FLUORIDES OF RHODIUM 107 GENERAL DISCUSSION 108 SUGGESTIONS FOR FURTHER INVESTIGATIONS 109 SUMMARY SUMMARY OF THE KNOWN FLUORIDES OF PLATINUM 110 APPENDICES 1. AN ALT/AC HIE COMPUTER PROGRAMME FOR THE DETERMINATION OF USEFUL FUNCTIONS FROM X-RAY POWDER PHOTOGRAPHS. 112 2. AN ALWAC HIE COMPUTER PROGRAMME FOR THE GRAPHICAL DETERMINATION OF ACCURATE LATTICE PARAMETERS FOR TETRAGONAL CRYSTALS 111 REFERENCES 121 (vi) LIST OF TABLES Page .• TABLE I. Tbe simple fluorides of Group VIII 10 TABLE II. Calculated and observed x-ray diffr&ctiom data for platinum, trifluoride.