  Hydrocarbons are observed in the gas or solid phases of solar system objects,
including comets, Trans-Neptunian Objects, planets and their moons. In the
presence of water ice in these environments, hydrocarbons-bearing clathrate
hydrates could form. In clathrate hydrates, guest molecules are trapped in
crystalline water cages of different sizes, a phase used in models of planetary
(sub-)surfaces or icy bodies such as comets. The phases in presence, the
potential estimate of abundances of hydrocarbon species, the spectroscopic
behaviour of hydrocarbon species in the different phases must be recorded to
provide reference spectra for the comparison with remote observations. We show
in this study the specific encaged ethylene signatures, with bands similar in
position, but shifted from the pure ethylene ice spectrum. They show a marked
temperature dependence both in position and width. Some vibrational modes are
activated in the infrared by interaction with the water ice cages.
