Novel graphite biintercalation compound with layers of SmCl3 and ErCl3 is s
ynthetized by the one-zone vapour method. A well defined stage-3 SmCl3 grap
hite intercalation compound with the c-axis repeat distance I-c = 16.60 +/-
0.07 Angstrom is used as the host matrix. The X-ray diffraction shows a cr
eation of a new compound with I-c = 19.70 +/- 0.058 Angstrom. Based on thes
e data a ...G-SmCl3-G-ErCl3... stacking sequence is proposed. The electron
diffraction shows a-axis of the intercalated layer is rotated with respect
to the graphene a-axis by 42 degrees, and 19 degrees, 42 degrees for SmCl3
and ErCl3 layers, respectively. The parameters of the lattices obtained are
a(SmCl3) = 7.37 Angstrom, a(ErCl3) = 6.75 Angstrom, and b(ErCl3) = 11.73 A
ngstrom.