The intercalation of molecular N-2 into C(24)X (X = K, Rb) has been st
udied using the nuclear resonance photon scattering (NRPS) technique.
We found that, in the physintercalated state, the nitrogen resides in
the alkali planes, in a molecular form, with the molecular symmetry ax
is almost parallel to the graphene basal planes. In C24K, the N-2 mole
cules are only intercalated below 200 K, while in the case of C24Rb, t
he physintercalation process starts at room temperature and the amount
of intercalated N-2 increases with decreasing T, reaching saturation
at around 130 K. These samples were also studied using n-diffraction a
nd the N-2 ''small'' diameter, at 120 K, was found to be 0.290 nm in t
he (C24K + N-2) system and slightly smaller, 0.279 nm, in the (C24Rb N-2) system. This difference in the measured diameters could also be
attributed to a smaller tilt angle of the N-2 molecule in C24Rb as com
pared to that in C24K.