  We have derived the stellar atmospheric parameters, the effective temperature
T$_{eff}$, the microturbulent velocity $\zeta$, the surface gravity log g, and
the metallicity [Fe/H] for HE 0017+0055, HE 2144-1832, HE 2339-0837, HD 145777,
and CD-27 14351 from local thermodynamic equilibrium analyses using model
atmospheres. Elemental abundances of C, N, $\alpha$-elements, iron-peak
elements, and several neutron-capture elements are estimated using the
equivalent width measurement technique as well as spectrum synthesis
calculations in some cases. In the context of the double enhancement observed
in four of the programme stars, we have critically examined whether the
literature i-process model yields ([X/Fe]) of heavy elements can explain the
observed abundance distribution. The estimated metallicity [Fe/H] of the
programme stars ranges from -1.63 to -2.74. All five stars show enhanced
abundance for Ba, and four of them exhibit enhanced abundance for Eu. Based on
our analysis, HE 0017+0055, HE 2144-1832, and HE 2339-0837 are found to be
CEMP-r/s stars, whereas HD 145777 and CD-27 14351 show characteristic
properties of CEMP-s stars. From a detailed analysis of different classifiers
of CEMP stars, using a large sample of similar stars from the literature, we
have identified the one which best describes the CEMP-s and CEMP-r/s stars. We
have also examined if [hs/ls] alone can be used as a classifier, and if there
are any limiting values for [hs/ls] ratio that can be used to distinguish
CEMP-s and CEMP-r/s stars. In spite of peaking at different values of [hs/ls],
CEMP-s and CEMP-r/s stars show an overlap in the range 0.0 < [hs/ls] < 1.5 and
hence this ratio alone can not be used to distinguish CEMP-s and CEMP-r/s
stars.
