*HEADING
EC36EFE1: EIGENVALUE ANALYSIS OF AN UNCONSTRAINED 1-ELEMENT MESH  [C3D6E]
*PREPRINT,ECHO=YES,HISTORY=YES,MODEL=YES
*NODE,NSET=ALL
  1, 0.0, 0.0, 0.0
  2, 2.0, 0.0, 0.0
  3, 2.0, 2.0, 0.0
  4, 0.0, 2.0, 0.0
  5, 0.0, 0.0, 1.0
  6, 2.0, 0.0, 1.0
  7, 2.0, 2.0, 1.0
  8, 0.0, 2.0, 1.0
*ELEMENT,TYPE=C3D6E, ELSET=EALL
 1, 1,2,4,5,6,8
*SOLID SECTION,MATERIAL=A1, ELSET=EALL
*MATERIAL,NAME=A1
*ELASTIC
 3.E6,0.3
*PIEZOELECTRIC,TYPE=S
15.08,-5.207,-5.207,0.,0.,0.,0.,0.
0.,12.710,0.,0.,0.,0.,0.,0.,
12.710,0.
*DIELECTRIC,TYPE=ISO
5.872E-9, 
*DENSITY
7.5E-4, 
*STEP,PERTURBATION
FIRST STEP RESTRAINS ALL EPOT, COMPARE WITH C3D611 RESULTS
*FREQUENCY, eigensolver=lanczos, SIM=NO
9, , ,-1.E6 
*BOUNDARY
ALL,9
*END STEP
*STEP,PERTURBATION
SECOND STEP RELEASES ALL BUT ONE EPOT
*FREQUENCY, eigensolver=lanczos, SIM=NO
9, , ,-1.E6 
*BOUNDARY
1,9
*END STEP