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Monte Carlo calculations of the O Kalpha line fluoresced by coronal X-raysand emitted just above the temperature minimum region of the solar atmospherehave been employed to investigate the use of this feature as an abundancediagnostic. While quite weak, we estimate line equivalent widths in the range0.02-0.2 AA, depending on the X-ray plasma temperature. The line remainsessentially uncontaminated by blends for coronal temperatures T =< 3e6 K andshould be quite observable, with a flux >~ 2 ph/s/arcmin^2. Model calculationsfor solar chemical mixtures with an O abundance adjusted up and down by afactor of 2 indicate 35-60% changes in O Kalpha line equivalent width,providing a potentially useful O abundance diagnostic. Sensitivity ofequivalent width to differences between recently recommended chemicalcompositions with ``high'' and ``low'' complements of the CNO trio importantfor interpreting helioseismological observations is less accute, amounting to20-26% at coronal temperatures T ~< 2e6 K. While still feasible fordiscriminating between these two mixtures, uncertainties in measured lineequivalent widths and in the models used for interpretation would need to besignificantly less than 20%. Provided a sensitive X-ray spectrometer withresolving power >= 1000 and suitably well-behaved instrumental profile can bebuilt, X-ray fluorescence presents a viable means for resolving the solar``oxygen crisis''.

On the Detectability of Oxygen X-ray Fluorescence and its Use as a Solar Photospheric Abundance Diagnostic