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Stephen E. Haggerty

Publications and source records attributed to Stephen E. Haggerty.

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Infrared Absorption Investigations Confirm the Extraterrestrial Origin of Carbonado-Diamonds

The first complete infrared FTIR absorption spectra for carbonado-diamond confirm the interstellar origin for the most enigmatic diamonds known as carbonado. All previous attempts failed to measure the absorption of carbonado-diamond in the most important IR-range of 1000-1300 cm-1 (10.00-7.69 micro-m.) because of silica inclusions. In our investigation, KBr pellets were made from crushed silica-free carbonado-diamond and thin sections were also prepared. The 100 to 1000 times brighter synchrotron infrared radiation permits a greater spatial resolution. Inclusions and pore spaces were avoided and/or sources of chemical contamination were removed. The FTIR spectra of carbonado-diamond mostly depict the presence of single nitrogen impurities, and hydrogen. The lack of identifiable nitrogen aggregates in the infrared spectra, the presence of features related to hydrocarbon stretch bonds, and the resemblance of the spectra to CVD and presolar diamonds indicate that carbonado-diamonds formed in a hydrogen-rich interstellar environment. This is consistent with carbonado-diamond being sintered and porous, with extremely reduced metals, metal alloys, carbides and nitrides, light carbon isotopes, surfaces with glassy melt-like patinas, deformation lamellae, and a complete absence of primary, terrestrial mineral inclusions. The 2.6-3.8 billion year old fragmented body was of asteroidal proportions.

physics.space-ph

Investigating the optical properties of carbonado-diamonds

Carbonado-diamond is the most enigmatic of diamond types, and surprisingly there are few optical studies. In some cases, the diamond peak at 1332.5 cm-1 is absent, and the presence of a D-band graphite peak around 1320 cm-1 is observed in our Raman investigation. The disappearance of the diamond peak in carbonado-diamond is interpreted as the combined effect of small crystal size and the high absorption of graphite. The photoluminescence spectra of carbonado-diamond shows two new zero phonon lines at 584.2 nm (2.12 eV) and at 743 nm (1.67 eV). By heating the carbonado-diamond to 1500 oC for ten minutes in argon the appearance of an additional peak at 693.5 nm (1.786 eV) is detected. The infrared absorption spectra of carbonado-diamond powder indicate either extremely low or extremely high absorption.

physics.geo-ph