quantum-computational

name: quantum-computational description: Quantum computing for computational chemistry license: MIT compatibility: opencode metadata: audience: quantum chemists, computational scientists, researchers category: chemistry

What I do

• Apply quantum computing to chemical problems
• Simulate quantum systems on quantum hardware
• Develop quantum algorithms for chemistry
• Calculate strongly correlated systems
• Research quantum machine learning
• Explore quantum advantage in chemistry

When to use me

• When simulating quantum chemistry problems
• When exploring quantum computing applications
• When calculating strongly correlated systems
• When developing quantum algorithms
• When studying quantum advantage
• When modeling molecular quantum dynamics

Key Concepts

Quantum Computing Basics

Qubits: |0⟩, |1⟩, or superposition Quantum Gates: Hadamard, CNOT, Pauli, rotation Quantum Circuits: Sequence of gates

Variational Quantum Eigensolver (VQE)

# Example: VQE framework for quantum chemistry
def vqe(ansatz, hamiltonian, optimizer):
    """
    Find ground state energy using quantum computer.
    ansatz: Parameterized quantum circuit
    hamiltonian: Molecular Hamiltonian
    optimizer: Classical optimizer
    """
    def objective(params):
        # Prepare quantum state
        state = ansatz.apply(params)
        
        # Measure expectation value
        energy = hamiltonian.expectation(state)
        
        return energy
    
    return optimizer.minimize(objective)

# Ansatz circuits
ansatz_types = {
    'UCCSD': 'Unitary coupled cluster',
    'Hardware Efficient': 'Hardware-adapted layers',
    'ADAPT': 'Iterative ansatz construction'
}

Quantum Chemistry on Quantum Computers

• Hamiltonian mapping: Jordan-Wigner, Bravyi-Kitaev
• State preparation: Adiabatic, variational
• Measurement reduction: Grouping techniques
• Error mitigation: ZS, PEC, TMR

Applications

• Ground state energy
• Excited states
• Molecular dynamics
• Reaction rates
• Excited states
• Catalyst design

Available Frameworks

• Qiskit Nature
• Cirq
• PennyLane
• Amazon Braket
• IBM Quantum