This study tests the current state-of-the art development in theoretical calculations of X-ray absorption fine structure (XAFS) against recently collected in-situ XAFS structural measurements of electrochemically deposited copper on a pristine platinum(111) surface. From the in-situ measurements, copper-copper and copper-oxygen bond distances were found to be. 2.77 +/- 0.03 and 2.1 +/- 0.03 Angstrom, respectively. Employing an automated ab-initio code, FEFF, developed by Rehr and co-workers(5) to calculate theoretical XAFS standards, qualitative agreement was found with our experimental findings. Using the FEFF calculations, we examined copper electrodeposited on 3-fold hollow sites and on bridge sites of the platinum substrate. The FEFF calculations for Cu on 3-fold hollow sites of Pt(111) closely match the experimental data which indicates that the deposited Cu adatoms reside in 3-fold hollow sites of the Pt(111) surface, which represents the most stable arrangement.