CONTENTS. 



PAGE. 



Chapter I. Introduction 1 



Recent Spectroscopic Investigations 1 



Spectra of Gases 3 



Spectra of Liquids and Solids 6 



Banded Spectra 7 



A Method of Chemical Analysis 8 



Atomic Structure and Spectra 9 



Organic Absorption Spectra The Unit of this Absorption 10 



The Theory of Chromophores 11 



Theory of Dynamic Isomerism 12 



Theory of Stark 13 



Complexity of the Problem of the Spectra of Compounds 13 



Method of Attacking the Problem of Emission and Absorption Spectra 16 



Chapter II. Experimental Methods 19 



Chapter III. Potassium Salts 23 



Potassium Chromate 25 



Potassium Dichromate 26 



Potassium Ferrocyanide in Water 27 



Potassium Ferricyanide in Water 28 



Chapter IV. Cobalt Salts 31 



Review of Previous Work 31 



Glycerol Solutions of Cobalt Salts 34 



Aqueous Solutions of Cobalt Salts 34 



Cobalt Nitrate 37 



Cobalt Sulphate 38 



Cobalt Acetate 38 



Cobalt Chloride and Calcium Chloride 38 



Cobalt Chloride and Aluminium Chloride 39 



Cobalt Sulphocyanate 40 



Cobalt Chloride in Water, Conductivity and Dissociation 41 



Cobalt Bromide in Water, Conductivity and Dissociation 41 



Cobalt Nitrate in Water, Conductivity and Dissociation 41 



Summary 42 



Chapter V. Nickel Salts 43 



Intrr duction 43 



Nickel Chloride 43 



Nickel Sulphate 44 



Nickel Acetate 44 



Nickel Chloride in Water, Conductivity and Dissociation 45 



Nickel Nitrate in Water, Conductivity and Dissociation 45 



Chapter VI. Copper Salts 47 



Copper Bromide 47 



Copper Nitrate 47 



Chapter VII. Chromium Salts 49 



Introduction 49 



Chromium Chloride 51 



Chromium Chloride and Aluminium Chloride 52 



vii 



