Do cement nanoparticles exist in space ?
  The calcium-silicate-hydrate is used to model properties of cement on Earth.
We study cementitious nanoparticles and propose these structures as components
of cosmic dust grains. Quantum density functional theory methods are applied
for the calculation of infrared spectra of Ca4Si4O14H4, Ca6Si3O13H2, and
Ca12Si6O26H4 clusters. We find bands distributed over the near, mid and
far-infrared region. A specific calcium-silicate-hydrate spectral feature at 14
microns, together with the bands at 10 and 18 microns which exist for other
silicates as well, could be used for a detection of cosmic cement. We compare
calculated bands with the 14 microns features in the spectra of HD 45677, HD
44179, and IRC+10420 which were observed by Infrared Space Observatory and
classified as remaining. High abundance of oxygen atoms in cementitious
nanoparticles could partially explain observed depletion of this element from
the interstellar medium into dust grains.
