Matrix t2*K(2) in Subspace 117 with Dimension 4

(K(2) is the second-order Grosse operator)

(-9*t*U)/2 -(U^2/Sqrt[2]) 0 -U^2
-(U^2/Sqrt[2]) -3*t*U Sqrt[3/2]*t*U 0
0 Sqrt[3/2]*t*U (-3*t*U)/2 Sqrt[3]*t*U
-U^2 0 Sqrt[3]*t*U -3*t*U