EF values calculated at the 1650 cm⁻¹ peak from different concentrations of RhB using Ag₃Au NPs as a substrate.

RhB (M)	10−5	10−6	10−7	10−8	10−9	10−10	10−11
EF value	8.5 × 105	6.4 × 106	3.3 × 107	4.4 × 107	8 × 108	3 × 109	2 × 1010