Temperature dependence of thermodynamic function in Zn₄SnSe₆ and Zn₄SnSe₆:Co²⁺(0.5mol%) single crystals

Zn₂SnSe₆ 및 Zn₄SnSe₆:Co²⁺(0.5mol%) 단결정에서 열역학적 함수의 온도의존성

$Zn_4SnSe_6$ and $Zn_4SnSe_6:Co^{2+}$ single crystals were grown by the chemical transport reaction(CTR) method. They were crystallized in the monoclinic structure. These temperature dependence of the optical energy gap were closely investigated over the temperature range 10[K]~300[K]. The direct energy gaps of $Zn_4SnSe_6$ and $Zn_4SnSe_6$:$Co^{2+}$ single crystals were given by 2.146[eV] and 2.042[eV] at 300[K]. The temperature dependence of the optical energy gap is well presented by the Varshni equation.