The emission from dark ages halos in the lines of transitions between lowest rotational levels of hydrogen and hydrogen deuteride molecules is analyzed .
It is assumed molecules to be excited by CMB and collisions with hydrogen atoms .
The physical parameters of halos and number density of molecules are precalculated in assumption that halos are homogeneous top-hat spheres formed from the cosmological density perturbations in the four-component Universe with post-Planck cosmological parameters .
The differential brightness temperatures and differential spectral fluxes in the rotational lines of H _ { 2 } -HD molecules are computed for two phenomena : thermal luminescence and resonant scattering of CMB radiation .
The results show that expected maximal values of differential brightness temperature of warm halos ( T _ { K } \sim 200-800 K ) are at the level of nanokelvins , are comparable for both phenomena , and are below sensitivity of modern sub-millimeter radio telescopes .
For hot halos ( T _ { K } \sim 2000-5000 K ) the thermal emission of H2-ortho molecules dominates and the differential brightness temperatures are predicted to be of a few microkelvins at the frequencies 300-600 GHz , that could be detectable with telescopes of a new generation .