Matrix t*K(1) in Subspace 136 with Dimension 4

(K(1) is the first-order Grosse operator)

0 0 I*Sqrt[6]*t 0
0 0 (I*(3*I + Sqrt[3])*U)/Sqrt[2] ((3 + I*Sqrt[3])*t)/Sqrt[2]
I*Sqrt[6]*t ((3 + I*Sqrt[3])*U)/Sqrt[2] (-I)*Sqrt[3]*t (I/2)*(3*I + Sqrt[3])*U
0 (I*(3*I + Sqrt[3])*t)/Sqrt[2] ((3 + I*Sqrt[3])*U)/2 (-I)*Sqrt[3]*t