Elemental (C, H, N) analysis was obtained using a Perkin–Elmer
Elemental Analyzer 2400 CHN. Infrared spectra of the solid samples
were recorded using a Perkin–Elmer Spectrum 100, equipped
with a Specac Golden Gate Diamond ATR as a solid sample support.
Electronic spectra with nujol suspensions were measured by a Perkin–
Elmer UV/VIS/NIR Spectrophotometer Lambda 19. X-ray powder
diffraction data were obtained using PANalytical X’Pert PRO
MPD with Cu Ka radiation (k = 1.5406 Å). The magnetic susceptibility
data of powdered samples were measured with a Johnson
Matthey Alfa Products Sherwood Scientific Magnetic Balance, using
Evans’s method. Diamagnetic corrections were estimated from
Pascal’s constants [24]. X-band powder EPR spectra were obtained
at various temperatures with a Bruker ELEXSYS E500 spectrometer.
The spectra of 1 and 2 were measured by the solid samples on the
bottom of the closed tube in the presence of the mother liquid,
while the final products 1a and 2a as a dry powder.
Single-crystal X-ray diffraction data were collected with a Nonius
Kappa CCD diffractometer with the graphite monochromated
Mo Ka radiation (k = 0.71073 Å) at room temperature for 1 and
at 150 K for 2, respectively. A multiscan absorption correction
was performed [25]. The structures were solved by direct methods
(SHELXS-97 [26] for 1 and SIR-97 [27] for 2) and refined by a full-matrix
least-squares procedure based on F2 (SHELXL-97) [26]. Hydrogen
atoms attached to N2 atoms in 2 were visible in the last stages of
refinement and were refined freely. All the remaining H atoms in
both structures were placed at calculated positions and treated
using appropriate riding models. The atoms of CH3CN molecules
in 2 were refined isotropically and the H atoms of those molecules
were not located. The residual density peak in structure of 2 (in the
vicinity of CH3CN molecule) was undefinable and therefore was
not included in the model. The crystal data and details of the data
collection and refinement are collected in Table 1.