Pointers toward the Occurrence of C−F···F−C Interaction: Experimental Charge Density Analysis of 1-(4-Fluorophenyl)-3,6,6-trimethyl-2-phenyl-1,5,6,7-tetrahydro-4H-indol-4-one and 1-(4-Fluorophenyl)-6-methoxy-2-phenyl-1,2,3,4-tetrahydroisoquinoline | doi.page