The phonon properties of BiFeO₃ have been studied by using the specific heat. It is found that the specific heat of BiFeO₃ exhibits two peaks. The first peak appears at the magnetic phase transition temperature T_N = 650 K. This anomaly in specific heat can be interpreted as antiferromagnetic transition. The values of the specific heat (at the magnetic phase transition temperature T_N) increase with the increasing of the J₁, |J₂|, I and g. Another abnormal peak of specific heat appears at nearly 550 K, which is associated with the onset of structural changes. Note that the second peak shifts to lower temperature as the J₁, |J₂|, I and g decrease. It is considered that the main reason of leading to the structure distortion increases is due to the increase of the J₁, |J₂|, I and g. Those calculation conclusions are in accordance with the experimental results of other researchers.

已经通过使用比热研究了BiFeO ₃的声子性质。发现BiFeO ₃的比热表现出两个峰。第一个峰值出现在磁性相变温度T _N  = 650 K处。比热中的这种异常现象可以解释为反铁磁转变。比热的值（在磁相转变温度Ť _Ñ）与所述的增加而增加Ĵ ₁，| J ₂ |，I和g。比热的另一个异常峰值出现在近550 K，这与结构变化的开始有关。请注意，随着J ₁，| |的第二个峰移至较低温度。J ₂ |，I和g减小。认为导致结构变形增加的主要原因是由于J ₁，|的增加。J ₂ |，I和g。这些计算结论与其他研究人员的实验结果一致。