structure of the compound. The positions of the Ni and Cl atoms are shown.](figure3){width="6cm"}

Initially, to provide magnetic characterization, the magnetic susceptibitilies of a single crystal were measured in the directions parallel and perpendicular to the $c$-axis, and temperatures ranging from 0.4 to 300 K.

From these data the parameters applicable to the following $S=1$ spin-Hamiltonian with single-ion anisotropy were determined: $${\cal H} = \sum_{{\bf j},\nu}J_{\nu}{\bf S}_{\bf j}
\cdot {\bf S}_{{\bf j}+e_{\nu}} + \sum_{{\bf j}}[D(S^z_{\bf j})^2
- g\mu_{B}HS^z_{\bf j}].
\label{eq:H}$$

The obtained parameters are $g$= 2.30 and $D$ $\approx \ 9$ K. Molecular field correction gives the exchange interaction parameter $J$ $ \approx \ - 2.2$ K (antiferromagnetic). The high $D$ value and the anisotropy in the exchange suggest a quasi 1D behavior. These data were used to anticipate an induced ordered phase at low temperature in an applied magnetic field below $\approx \ 11$ T.

3.1. Magnetic Induced Phase Diagram - BEC
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The field-induced phase by level crossing is permitted in compounds that follow stringent requirements: in addition to having a multiplet above the non-magnetic singlet, the metal ion must reside in a site of uniaxial symmetry, so that the magnetic field can be applied simultaneously parallel to 