Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology
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Geometry for Si₂H₄ (Disilene) ¹A_G C2H

QCISD(T)/6-311+G(3df,2p)

For information on specific bond angles or dihedrals see the geometry comparison page in section Comparisons > Geometry > Bonds, angles.