David T. Hardy has posted The Meaning of 'Emoluments' as Employed in the Constitution of the United States on SSRN. Here is the abstract:
The Constitution forbids any federal official's receipt of "emoluments" from a foreign government. This rarely-invoked provision has recently come to prominence, with the argument that the president's interest in his hotel chain, which receives room rentals from foreign officials, violates the prohibition. This paper explores the meaning of the term as it was understood at the time of the Framing. It concludes that the predominant understanding of the term was compensation (including perquisites and "fringe benefits") from holding an office.