Development of a technique for IR spectroscopic determination of nitrogen content and aggregation degree in diamond crystals

Morphology and spectral characteristics of octahedral diamond crystals from Yubileinaya diamond pipe (Yakutiya)

“…Data on the nitrogen contents of diamond structural defects are taken in a Thermo Nickolet IR200 IR Fourier spectrometer. The traditional methods of processing IR spectra [3,10,[12][13][14][15] in the majority of cases are restricted to the calculation of the nitrogen concentration only in the form of A and B(B1) defects as they usually overlap the bands of C defects and for a band of planar B2(P) defect the relation between the nitrogen concentration and peak intensity and absorption coefficient is not established.…”

“…In the present study the new techniques of processing IR spectra developed by us for the calculation of the concentration of nitrogen defects by decomposing them into the components using the OMNIC and Origi PRODUCTION, STRUCTURE, PROPERTIES nalpro 7.0 computer programs with a subsequent separation and calculation of the areas of A , B1 , C , and B2 defects followed by the normalization relative to the integral area of fundamental absorption bands [3].…”

“…However, in spite of the achievements in the field [1][2][3][4][5][6][7], some problems of the genetic interpretation of morphological and IR spectroscopic data remain unre solved. There is no a total clarity as to the origination of rounded diamonds and most abundant plane-face diamond crystals of octahedral habit and crystals with relief faces, for which the relation with the concentra tion of nitrogen and other defects turned out to be not adequately explored and criteria of their belonging to a certain form are not defined [8,9].…”

“…There is no a total clarity as to the origination of rounded diamonds and most abundant plane-face diamond crystals of octahedral habit and crystals with relief faces, for which the relation with the concentra tion of nitrogen and other defects turned out to be not adequately explored and criteria of their belonging to a certain form are not defined [8,9]. In the assessment of the equilibrium temperature from the nitrogen aggre gation degree [3,4,[10][11][12][13][14] the variations of the nitrogen concentrations in different types of defects in micro and macrocrystals within the limits of separate zonal sectorial structures and depending on the crystal size were not allowed for. The problems of increasing sensitivity, precision, and locality of IR spectroscopic stud ies, improvement of methods of processing IR spectra, and calculation of a nitrogen impurity and degree of its aggregation in the main defects as well as methods of the presentations of experimental and calculated data remain [14].…”