Mechanical and electronic properties of endofullerene Ar@C60 and Kr@C60 studied via structure distortions

Elastic, strength, electronic properties and vibrational spectra of Ar@C60 and Kr@C60 (Ih) in their ground electronic state (X 1Ag) were investigated with density functional theory at B3PW91/6-31G level via structure distortions. The elastic properties were obtained from the potential energy curves (PECs) in all of the five independent distortional directions of the molecules with symmetries of (1) D5d, (2) D3d, (3) D2h, (4) C2h(1) and (5) C2h(2). PECs were examined towards where the structures of Ar@C60 and Kr@C60 were destroyed. The necessary energies to destroy the structures were thus obtained, which illuminated the stability of Ar@C60 and Kr@C60. PECs were found to be anisotropy and were accurately fitted into polynomials. Elongations in the direction of D5d and compression in D2h encountered potential energy surface cross-linkages, which might be considered as a single electron pump for further application in the design of single electron devices. Time-dependent B3PW91/6-31G analysis predicted significant electronic spectra changes associated with structure distortions. Similarities and differences of the properties were compared with those in C60, He@C60 and Ne@C60.