Investigation of Cycloparaphenylenes (CPPs) and their Noncovalent Ring-in-Ring and Fullerene-in-Ring Complexes by (Matrix-Assisted) Laser Desorption/Ionization and Density Functional Theory

n]Cycloparaphenylenes (n]CPPs) with n=5, 8, 10 and 12 and their noncovalent ring-in-ring and m]fullerene-in-ring complexes with m=60, 70 and 84 have been studied by direct and matrix-assisted laser desorption ionization ((MA)LDI) and density-functional theory (DFT). LDI is introduced as a straightforward approach for the sensitive analysis of CPPs, free from unwanted decomposition and without the need of a matrix. The ring-in-ring system of 10]CPP?5]CPP]^+. was studied in positive-ion MALDI. Fragmentation and DFT indicate that the positive charge is exclusively located on the inner ring, while in 10]CPP?C₆₀]^+. it is located solely on the outer nanohoop. Positive-ion MALDI is introduced as a new sensitive method for analysis of CPP?fullerene complexes, enabling the detection of novel complexes 12]CPP?C_{60, 70 and 84}]^+. and 10]CPP?C₈₄]^+.. Selective binding can be observed when mixing one fullerene with two CPPs or vice versa, reflecting ideal size requirements for efficient complex formation. Geometries, binding and fragmentation energies of CPP?fullerene complexes from DFT calculations explain the observed fragmentation behavior.