# Compute molecular vibrational energy of CO2 molecule using VQE

I have to compute the molecular vibrational energy of CO2 molecules using VQE, but I am not progressing; Code on the qiskit website does not work. Does anyone have any working code to find vibrational energy of any molecule using qiskit?

code source - qiskit Error-

    from qiskit_nature.second_q.problems import VibrationalStructureProblem
from qiskit_nature.second_q.mappers import DirectMapper

vibrational_problem = driver.run(basis=basis)
vibrational_problem.hamiltonian.truncation_order = 2
main_op, aux_ops = vibrational_problem.second_q_ops()
---------------------------------------------------------------------------
ValueError                                Traceback (most recent call last)
Cell In[9], line 4
1 from qiskit_nature.second_q.problems import VibrationalStructureProblem
2 from qiskit_nature.second_q.mappers import DirectMapper
----> 4 vibrational_problem = driver.run(basis=basis)
5 vibrational_problem.hamiltonian.truncation_order = 2
6 main_op, aux_ops = vibrational_problem.second_q_ops()

File /opt/homebrew/lib/python3.11/site-packages/qiskit_nature/second_q/drivers/gaussiand/gaussian_forces_driver.py:153, in GaussianForcesDriver.run(self, basis)
150 else:
151     glr = GaussianLogDriver(jcf=self._jcf).run()
--> 153 watson = glr.get_watson_hamiltonian(normalize=self._normalize)
155 problem = watson_to_problem(watson, basis=basis)
156 return problem

File /opt/homebrew/lib/python3.11/site-packages/qiskit_nature/second_q/drivers/gaussiand/gaussian_log_result.py:287, in GaussianLogResult.get_watson_hamiltonian(self, normalize)
280     watson = WatsonHamiltonian(