**Determination of the Distributions of the Spin-Hamiltonian Parameters in Spin Triangles: A Combined Magnetic Susceptometry and Electron Paramagnetic Resonance Spectroscopic Study of the Highly Symmetric [Cr _{3}O(PhCOO)_{6}(py)_{3}](ClO_{4})·0.5py**

*Inorganic Chemistry, 2018.*Abstract:

Magnetic susceptibility and X-band electron paramagnetic resonance (EPR) studies have been carried out on the highly symmetric [Cr_{3}O(PhCOO)_{6}(py)_{3}](ClO_{4})·0.5py (**1**; py = pyridine), whose cation exhibits a *D*_{3h} crystallographically imposed molecular symmetry. While magnetic susceptibility data can be interpreted with an equilateral magnetic model described by the effective multispin Hamiltonian *Ĥ* = −2*J*(**Ŝ**_{1}·**Ŝ**_{2} + **Ŝ**_{2}·**Ŝ**_{3} + **Ŝ**_{3}·**Ŝ**_{1}), EPR data require an isosceles model described by the multispin Hamiltonian *Ĥ* = −2*J*(*Ŝ*_{1}·*Ŝ*_{2} + *Ŝ*_{2}·*Ŝ*_{3}) – 2*J*′*Ŝ*_{3}·*Ŝ*_{1}, where Δ*J* = *J* – *J*′ ≠ 0. Moreover, EPR data reveal the interplay of antisymmetric exchange (or Dzyaloshinskii–Moriya) interactions, described by a 2**G**(**Ŝ**_{1} × **Ŝ**_{2} + **Ŝ**_{2} × **Ŝ**_{3} + **Ŝ**_{3} × **Ŝ**_{1}) term, which induce significant anisotropy to the *S*_{T} = ^{1}/_{2} ground state of **1**, as well as an important broadening of the *g*_{⊥} resonance (*g* strain). Through careful analysis of these data and in conjunction with neutron scattering data, this *g* strain can be deconvoluted into distributions of the individual spin-Hamiltonian parameters Δ*J* and |**G**|. This method of analysis provides simultaneous estimates of the central values and distribution profiles of the spin-Hamiltonian parameters, which are shown not to be described by monodisperse values.