Powder neutron diffraction measurements were carried out on the HB-2A neutron diffractometer at the High Flux Isotope Reactor (HFIR), Oak Ridge National Laboratory (ORNL). A germanium monochromator was used to select λ = 2.41 Å from the Ge(113) reflection and λ = 1.54 Å from the Ge(115) reflection. The premono, presample, and predetector collimation was open-21'-12'. A pyrolytic graphite (PG) filter was placed before the sample to remove higher order reflections for λ = 2.41 Å. The samples were contained in a 6 mm diameter vanadium can and cooled in a liquid He cryostat with an in situ 3-sample changer stick in the temperature range 1.5 K to 300 K. The diffraction patterns were collected by scanning a 120 • bank of 44 He detectors in 0.05 • steps to give 2θ coverage from 5 • to 130 • . The magnetic structures were determined by refinement against data from which background and nuclear Bragg peaks were removed by subtraction of data collected at T > T N from those collected at T = 1.5 or 2 K. The magnetic Bragg peaks were indexed to determine the magnetic propagation vector and then the allowed magnetic irreducible representations were determined using symmetry-mode analysis on the ISODISTORT software. Using the scale factor determined from Rietveld refinement of the nuclear structure, and peak parameters determined from Pawley refinement of the nuclear structure, the direction and magnitude of the ordered moment for the subtracted dataset were refined using TOPAS-ACADEMIC 6.0. FeCl 2 (pym) Diffraction patterns were collected at T = 1.5, 12.5 and 25 K with λ = 2.41 Å for 4 h, 4h and 2h, respectively, and at T = 1.5 and 12.5 K with λ = 1.54 Å for 4 h each. Additional patterns were collected for 1 h at λ = 2.41 Å at intermediate temperature points T = 5, 6, 7, 8, 9, 9.5, 10, 10.5, 11, 12, 13, 14 and 15 K.