In[]:=
rg=RandomGraph[{10,20}]
Out[]=
In[]:=
Eigensystem[N[AdjacencyMatrix[rg]],-2,Method"Arnoldi"]
Out[]=
{{0.267395,-3.15544×},{{-0.0409192,0.369552,-0.101108,-0.683069,0.0994066,0.328633,0.395184,-0.172987,-0.280594,0.0473442},{-0.57735,-0.57735,-5.55112×,0.,-2.77556×,0.57735,5.55112×,-5.55112×,0.,5.55112×}}}
-30
10
-17
10
-17
10
-17
10
-17
10
-17
10