Matrix t*K(1) in Subspace 144 with Dimension 3

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

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