gap size (nm) SERS enhancement 6.96477123062947 24365776.8833155 8.42159427392401 45799931.9242381 6.23685183418988 41371062.9033288 5.90193894351239 44541410.7769565 5.62139472616654 48967384.3240497 4.65652183917669 63363607.9194891 4.33551526305336 57236325.4459719 7.35999586580153 86570430.0006042 4.58153948716391 111399282.543441 4.37084921546223 150093414.835895 2.47231297602235 149051524.557812 1.89136340041688 116802963.730304 3.3383536046311 196945046.68096 3.58552917558202 176665478.027976 2.45232679376615 236377274.930257 2.94130930517361 263511207.538158 2.94130930517361 293759865.531514 2.21392048763716 338615525.871892 2.19602315069163 369678836.506603 2.53325415415538 459421513.062404 1.81614055061891 444314300.015438 1.57693076869968 512158868.536753 1.86090743324392 537002325.149841 1.96650694786377 552175369.07799 2.30187917350881 658131190.015562 1.12139396349805 686220628.518643 1.33412174412845 759682151.377185 1.02894485553849 754408732.494558 0.698058914449413 1157057572.86344 0.703748014582893 1125263171.36783 0.774485734063612 857572174.705492 0.630196161541707 481706821.641545 0.630196161541707 395796277.612152 0.981626989614421 417896169.369887 0.891970006183989 291720698.46797 1.24416952354131 291720698.46797 1.57693076869968 270579513.725112 1.31477147581669 243056133.862818 1.70472227447886 236377274.930257