Matrix t*K(1) in Subspace 50 with Dimension 12

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

((-I/2)*t)/Sqrt[3] (I/12)*(11*I + Sqrt[3])*U 0 (-I/2 + 1/Sqrt[3])*t ((-2*I)*t)/Sqrt[3] -((3*I + Sqrt[3])*U)/6 0 (1 - (I/2)*Sqrt[3])*t (1/Sqrt[2] + I/Sqrt[6])*t (Sqrt[2]*U + I*Sqrt[6]*U)/6 (I - 1/(2*Sqrt[3]))*t ((3*I + Sqrt[3])*U)/4
((11 + I*Sqrt[3])*U)/12 ((-I/2)*t)/Sqrt[3] (-I/2 + 1/Sqrt[3])*t 0 0 (-I + 1/Sqrt[3])*t (-3*t)/2 0 (Sqrt[2]*(1 - I*Sqrt[3])*U)/3 (-(1/Sqrt[2]) + I/Sqrt[6])*t ((-3*I + Sqrt[3])*U)/12 (-I/2 - 1/Sqrt[3])*t
0 (-I/2 - 1/Sqrt[3])*t (I/2)*Sqrt[3]*t (U - (3*I)*Sqrt[3]*U)/4 0 -t -(Sqrt[3]*t)/2 ((3*I + Sqrt[3])*U)/4 0 (Sqrt[2/3] - I*Sqrt[2])*t 0 (1 - (I/2)*Sqrt[3])*t
(-I/2 - 1/Sqrt[3])*t 0 (-U - (3*I)*Sqrt[3]*U)/4 (-I/2)*Sqrt[3]*t 0 0 -((-3*I + Sqrt[3])*U)/4 ((3*I)/2)*t (I/Sqrt[2] - 1/Sqrt[6])*t 0 t/2 0
((-2*I)*t)/Sqrt[3] 0 0 0 0 0 0 0 (-I)*Sqrt[2/3]*t 0 (-2*I)*t 0
((-3*I + Sqrt[3])*U)/6 (-I - 1/Sqrt[3])*t t 0 0 0 Sqrt[3]*t 0 -((-3*I + Sqrt[3])*U)/(3*Sqrt[2]) -((3*I + Sqrt[3])*t)/(3*Sqrt[2]) (U - I*Sqrt[3]*U)/2 0
0 (3*t)/2 (Sqrt[3]*t)/2 ((3*I + Sqrt[3])*U)/4 0 -(Sqrt[3]*t) (I/2)*Sqrt[3]*t ((3 - I*Sqrt[3])*U)/4 0 0 0 -(Sqrt[3]*t)/2
(-1 - (I/2)*Sqrt[3])*t 0 -((-3*I + Sqrt[3])*U)/4 ((3*I)/2)*t 0 0 (-I/4)*(-3*I + Sqrt[3])*U (I/2)*Sqrt[3]*t (I*(I + Sqrt[3])*t)/Sqrt[2] 0 (Sqrt[3]*t)/2 0
(-(1/Sqrt[2]) + I/Sqrt[6])*t -(Sqrt[2]*(1 + I*Sqrt[3])*U)/3 0 (I/Sqrt[2] + 1/Sqrt[6])*t (-I)*Sqrt[2/3]*t ((3*I + Sqrt[3])*U)/(3*Sqrt[2]) 0 ((1 + I*Sqrt[3])*t)/Sqrt[2] ((-I)*t)/Sqrt[3] (I/6)*(5*I + Sqrt[3])*U (I/Sqrt[2] + 1/Sqrt[6])*t 0
((I/3)*(I + Sqrt[3])*U)/Sqrt[2] (1/Sqrt[2] + I/Sqrt[6])*t -(Sqrt[2]*(3*I + Sqrt[3])*t)/3 0 0 ((-I)/Sqrt[2] + 1/Sqrt[6])*t 0 0 ((5 + I*Sqrt[3])*U)/6 ((-I)*t)/Sqrt[3] ((-3*I + Sqrt[3])*U)/(3*Sqrt[2]) (I/Sqrt[2] - 1/Sqrt[6])*t
((6*I + Sqrt[3])*t)/6 -((3*I + Sqrt[3])*U)/12 0 -t/2 (-2*I)*t (-U - I*Sqrt[3]*U)/2 0 -(Sqrt[3]*t)/2 (I/Sqrt[2] - 1/Sqrt[6])*t -((3*I + Sqrt[3])*U)/(3*Sqrt[2]) (I/2)*Sqrt[3]*t (I/4)*(3*I + Sqrt[3])*U
-((-3*I + Sqrt[3])*U)/4 (-I/2 + 1/Sqrt[3])*t (-1 - (I/2)*Sqrt[3])*t 0 0 0 (Sqrt[3]*t)/2 0 0 (I/Sqrt[2] + 1/Sqrt[6])*t ((3 + I*Sqrt[3])*U)/4 (-I/2)*Sqrt[3]*t