Magnetic, thermal and ferroelectric properties of MOFs (metal organic frameworks), in particular, the compounds CH₃NH₂NH₂M(HCOO)₃ (MHyM) with M = Fe and Mn, are studied close to phase transitions. For the magnetic properties, the molecular field theory at low temperatures and the power-law formula within the framework of an Ising pseudospin-phonon coupled model close to ${\mathrm{T}}_{\mathrm{C}}$ are performed by using the observed magnetization data for MHyFe and MHyMn from the literature. For the thermal properties, particularly, the heat capacity ${\mathrm{C}}_{\mathrm{P}}$, Ising compressible model with the power-law formula is introduced to analyze the experimental data by considering the two anomalies in ${\mathrm{C}}_{\mathrm{P}}$ at the critical temperatures (${\mathrm{T}}_{\mathrm{C}1}$and ${\mathrm{T}}_{\mathrm{C}2}$) for MHyFe and MHyMn. Within these two anomalies, the ferroelectric properties of MHyMn are also studied by analyzing the observed data for the spontaneous polarization ${\mathrm{P}}_{\mathrm{S}}$ using the power-law formula.

Our calculations show that the molecular field theory is satisfactory for the temperature dependence of the magnetization at low temperatures well below ${\mathrm{T}}_{\mathrm{C}}$ at constant fields, with the M(T) at 0.1 kOe close to ${\mathrm{T}}_{\mathrm{C}}$ in MHyFe. Values of the critical exponent $\beta$ for the magnetization from our analysis using the power-law formula close to ${\mathrm{T}}_{\mathrm{C}}(=$ ${\mathrm{T}}_{\mathrm{m}})$, are acceptable for both compounds (MHyFe and MHyMn). Regarding the thermal properties, an Ising compressible model is adequate to describe the observed behaviour of the heat capacity ${\mathrm{C}}_{\mathrm{P}}$ with the two anomalies (${\mathrm{T}}_{\mathrm{C}1}$and ${\mathrm{T}}_{\mathrm{C}2}$) for MHyFe and MHyMn. Also, for the ferroelectric properties of those compounds the temperature dependence of the spontaneous polarization ${\mathrm{P}}_{\mathrm{S}}$ at ${\mathrm{T}}_{\mathrm{C}1}$and ${\mathrm{T}}_{\mathrm{C}2}$ (MHyMn) is studied by the power-law formula from an Ising compressible model which describes the observed behaviour of ${\mathrm{P}}_{\mathrm{S}}$ in this compound.

MOFs（金属有机骨架）的磁、热和铁电特性，特别是化合物 CH ₃ NH ₂ NH ₂ M(HCOO) ₃ (MHyM)，其中 M = Fe 和 Mn，研究接近于相变。对于磁性，低温下的分子场理论和Ising赝自旋声子耦合模型框架内的幂律公式接近于${\mathrm{吨}}_{\mathrm{C}}$使用从文献中观察到的 MHyFe 和 MHyMn 的磁化数据进行。对于热性能，特别是热容量${\mathrm{C}}_{\mathrm{磷}}$, 引入具有幂律公式的 Ising 可压缩模型对实验数据进行分析，考虑到 ${\mathrm{C}}_{\mathrm{磷}}$ 在临界温度（${\mathrm{吨}}_{\mathrm{C}1}$和 ${\mathrm{吨}}_{\mathrm{C}2}$) 为 MHyFe 和 MHyMn。在这两个异常中，还通过分析自发极化的观测数据来研究 MHyMn 的铁电性质${\mathrm{磷}}_{\mathrm{秒}}$ 使用幂律公式。

我们的计算表明，分子场理论对于低温下磁化强度的温度依赖性是令人满意的。 ${\mathrm{吨}}_{\mathrm{C}}$ 在恒定场，M(T) 为 0.1 kOe 接近 ${\mathrm{吨}}_{\mathrm{C}}$在MHyFe中。临界指数的值$\beta$ 对于我们使用幂律公式进行分析的磁化强度接近于 ${\mathrm{吨}}_{\mathrm{C}}(=$ ${\mathrm{吨}}_{\mathrm{米}})$, 对两种化合物（MHyFe 和 MHyMn）都是可接受的。关于热性能，Ising 可压缩模型足以描述观察到的热容量行为${\mathrm{C}}_{\mathrm{磷}}$ 与两个异常（${\mathrm{吨}}_{\mathrm{C}1}$和 ${\mathrm{吨}}_{\mathrm{C}2}$) 为 MHyFe 和 MHyMn。此外，对于这些化合物的铁电性质，自发极化的温度依赖性${\mathrm{磷}}_{\mathrm{秒}}$ 在 ${\mathrm{吨}}_{\mathrm{C}1}$和 ${\mathrm{吨}}_{\mathrm{C}2}$ (MHyMn) 由 Ising 可压缩模型的幂律公式研究，该模型描述了观察到的行为 ${\mathrm{磷}}_{\mathrm{秒}}$ 在这个化合物中。