Compound

$E_g^{PBE}$

$E_g^{BJ}$

$E_g^{mBJ}$

$E_g^{exp}$

TaCu₃S₄

1.935

2.055

2.148

2.7 [28]

TaCu₃Se₄

1.616

1.672

1.820

2.35 [28]

TaCu₃Te₄

1.162

1.194

1.311

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TaTl₃S₄

2.543

2.770

3.288

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TaTl₃Se₄

2.254

2.461

2.761

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