Crystallographic defects in diamond

Labeling and Symmetry of Diamond Defects

• Diamond spectroscopy tradition uses numbered acronyms to label defect-induced spectra
• Some acronyms are confusing due to similarities
• Same labels given to different centers detected by EPR and optical techniques
• Lack of clear distinction between the meaning of labels GR, R, and TR
• Logical acronyms include N3 and H3
• Defect symmetry in crystals described by point groups
• Symmetries observed in diamond defects: tetrahedral, tetragonal, trigonal, rhombic, monoclinic, and triclinic
• Defect-induced infrared absorption occurs due to breaking of crystal symmetry
• Predicting optical properties based on defect symmetry is possible
• Alignment of defects with lower symmetry than tetrahedral observed in synthetic diamond growth

Extrinsic Defects in Diamond

• Elemental analyses of diamond reveal a wide range of impurities
• Impurities mostly originate from inclusions of foreign materials in diamond
• Inclusions can be nanometer-small and invisible in an optical microscope
• Virtually any element can be hammered into diamond by ion implantation
• Essential elements can be introduced into diamond through various methods

Detection Methods for Diamond Defects

• Different types of spectroscopy used to detect diamond defects: EPR, photoluminescence (PL), cathodoluminescence (CL), and infrared (IR), visible, and UV absorption
• Absorption spectrum used to identify defects and estimate their concentration
• Spectroscopy can distinguish natural from synthetic or enhanced diamonds
• EPR, PL, and CL are common techniques for defect detection
• Infrared absorption is a common tool to measure defect concentrations in diamond

Effects of Diamond Defects

• Defects in diamond affect material properties and determine diamond type
• Dramatic effects observed in diamond color and electrical conductivity
• Electronic band structure explains the effects of defects on material properties
• Defects can be detrimental or desirable depending on the application
• Understanding the effects of defects is crucial for various industries using diamond

Miscellaneous Points

• Diamond spectroscopy tradition uses numbered acronyms to label defect-induced spectra
• Some acronyms are confusing due to similarities
• Same labels given to different centers detected by EPR and optical techniques
• Lack of clear distinction between the meaning of labels GR, R, and TR
• Logical acronyms include N3 and H3
• Symmetries observed in diamond defects: tetrahedral, tetragonal, trigonal, rhombic, monoclinic, and triclinic
• Alignment of defects with lower symmetry than tetrahedral observed in synthetic diamond growth
• Elemental analyses of diamond reveal a wide range of impurities
• Impurities mostly originate from inclusions of foreign materials in diamond
• Inclusions can be nanometer-small and invisible in an optical microscope
• Virtually any element can be hammered into diamond by ion implantation
• Essential elements can be introduced into diamond through various methods
• Different types of spectroscopy used to detect diamond defects: EPR, photoluminescence (PL), cathodoluminescence (CL), and infrared (IR), visible, and UV absorption
• Absorption spectrum used to identify defects and estimate their concentration
• Spectroscopy can distinguish natural from synthetic or enhanced diamonds
• EPR, PL, and CL are common techniques for defect detection
• Infrared absorption is a common tool to measure defect concentrations in diamond
• Electronic band structure explains the effects of defects on material properties
• Understanding the effects of defects is crucial for various industries using diamond

Crystallographic defects in diamond Data Sources