序参量与应变耦合的Landau相变理论表述形式的修正

Ｌａｎｄａｕ理论是成熟的平均场理论，但在计算临界指数上，与实验明显不符，而且不能用于解释序参量与应变耦合后出现的一级相变．作者对Ｌａｎｄａｕ表述提出修正，用运筹学方法求得ｇ（Ｔ，η）展开式中η的非整幂次为２．７和５．５，取整为３和６，而不是Ｌａｎｄａｕ理论中的２和４。这样，求得的临界指数更接近于实验值，而且能解释序参量与应变耦合后出现的一级相变现象。

MODIFICATION OF LANDAU THEORY ON COUPLING OF ORDER PARAMETER WITH ELASTIC STRAIN

Landau theory, though successful as an average field one, does not coincident with experimental results in critical index and also can not explain first-order transition in structure transitions after coupling of order parameter with elastic strain. In this paper,through modifing expansion powers of Landau theroy,thus getting 2. 7 and 5. 5 or 3 and 6by rounding of as integer in powers,not 2 and 4 in Landau theory,we can obtain critical index more close to experimental results and explain the first order transition after coupling of order parameter with elastic strain.