This survey of 13 electrooptic materials includes both a review and compilation of all materials properties relevant to their use in linear (Pockels) electrooptic modulator applications. Information on actual electrooptic modulator design as well as applications for these materials, and data on materials exhibiting a quadratic (Kerr) electrooptic effect, are not included. With these restrictions in mind, every attempt was made to be as comprehensive as possible by utilizing all available sources of literature: books, periodicals, reports, and vendor literature. The files of the Electronic Properties Information Center and full resources of the Hughes Aircraft Company Library were searched for pertinent data, and approximately 1000 articles were reviewed for this pUblication. A brief Introduction to the survey is followed by a description of the Prin ciples of Electrooptic Modulation, emphasizing the importance of crystal symmetry on the electrooptic properties of materials, and including the relationships between the electrooptic, piezooptic, elastooptic and piezoelectric effects in crystals. The survey consists of 13 independent sections, each section covering the properties of one material: crystallographic, optical, electrooptic, photoelastic, piezoelectric, dielectric and thermal. References appearing in the text are listed at the conclusion of each section. Tables and Figures are numbered separately for each section. v TABLE OF CONTENTS INTRODUCTION . • . . . . . 1 PRINCIPLES OF ELECTROOPTIC MODULATION. 5 AMMONIUM DIHYDROGEN ARSENATE (ADA) . 15 AMMONIUM DIHYDROGEN PHOSPHATE (ADP).