Matrix H in Subspace 31 with Dimension 8

H is the Hamiltonian. Here we set µ=0. For grand-canonical calculations add -6µ to the main diagonal.
-2*h + U 0 0 0 0 0 Sqrt[2 - 2*Sqrt[2/11]]*t (-2*(11 + Sqrt[22])*t)/(11*Sqrt[2 + 2*Sqrt[2/11]])
0 -2*(h - U) 2*t 0 0 0 0 0
0 2*t -2*(h - U) -(Sqrt[2]*t) 0 0 ((11*Sqrt[4 - 4*Sqrt[2/11]] + 14*Sqrt[121 - 11*Sqrt[22]] - 22*Sqrt[22 - 2*Sqrt[22]])*t)/(22*Sqrt[52 - 8*Sqrt[22]]) ((1001*Sqrt[2 + 2*Sqrt[2/11]] + Sqrt[11 + Sqrt[22]]*(264 + 5*Sqrt[22]))*t)/(264*Sqrt[26 + 4*Sqrt[22]])
0 0 -(Sqrt[2]*t) -2*(h - U) 0 2*t 0 0
0 0 0 0 -2*(h - U) 0 -((33*Sqrt[2 - 2*Sqrt[2/11]] + 5*Sqrt[242 - 22*Sqrt[22]] - 22*Sqrt[11 - Sqrt[22]])*t)/(11*Sqrt[52 - 8*Sqrt[22]]) -((1001*Sqrt[4 + 4*Sqrt[2/11]] + 2*(132*Sqrt[2] + 5*Sqrt[11])*Sqrt[11 + Sqrt[22]])*t)/(264*Sqrt[26 + 4*Sqrt[22]])
0 0 0 2*t 0 -2*h + U ((11*Sqrt[2] - 2*Sqrt[11])*t)/(11*Sqrt[2 - 2*Sqrt[2/11]]) -((11*Sqrt[2] + 2*Sqrt[11])*t)/(11*Sqrt[2 + 2*Sqrt[2/11]])
Sqrt[2 - 2*Sqrt[2/11]]*t 0 ((11*Sqrt[4 - 4*Sqrt[2/11]] + 14*Sqrt[121 - 11*Sqrt[22]] - 22*Sqrt[22 - 2*Sqrt[22]])*t)/(22*Sqrt[52 - 8*Sqrt[22]]) 0 -((33*Sqrt[2 - 2*Sqrt[2/11]] + 5*Sqrt[242 - 22*Sqrt[22]] - 22*Sqrt[11 - Sqrt[22]])*t)/(11*Sqrt[52 - 8*Sqrt[22]]) ((11*Sqrt[2] - 2*Sqrt[11])*t)/(11*Sqrt[2 - 2*Sqrt[2/11]]) ((13*Sqrt[2] - 4*Sqrt[11])*(2*h - U))/(Sqrt[2]*(-13 + 2*Sqrt[22])) 0
(-2*(11 + Sqrt[22])*t)/(11*Sqrt[2 + 2*Sqrt[2/11]]) 0 ((1001*Sqrt[2 + 2*Sqrt[2/11]] + Sqrt[11 + Sqrt[22]]*(264 + 5*Sqrt[22]))*t)/(264*Sqrt[26 + 4*Sqrt[22]]) 0 -((1001*Sqrt[4 + 4*Sqrt[2/11]] + 2*(132*Sqrt[2] + 5*Sqrt[11])*Sqrt[11 + Sqrt[22]])*t)/(264*Sqrt[26 + 4*Sqrt[22]]) -((11*Sqrt[2] + 2*Sqrt[11])*t)/(11*Sqrt[2 + 2*Sqrt[2/11]]) 0 -2*h + U