H positions at 1.087*sin(109.5/2) 0. 1.087*cos(109.5/2)
geometry
symmetry group c2v
C 0.000000000 0.000000000 0.000000000
H 0.887531783 0.000000000 0.627579743
H -0.887531783 0.00000000 0.627579743
H 0.000000000 0.887531783 -0.627579743
H 0.000000000 -0.887531783 -0.627579743
end