Physical Chemistry

What I do

• Apply physics to chemical systems
• Study molecular structure and spectroscopy
• Analyze chemical thermodynamics
• Investigate reaction kinetics
• Research quantum chemistry
• Model chemical systems

When to use me

• When studying molecular spectroscopy
• When analyzing thermodynamic properties
• When investigating reaction rates
• When applying quantum mechanics to molecules
• When modeling chemical equilibria
• When studying phase transitions

Key Concepts

Thermodynamics

Laws

1. Energy conservation
2. Entropy increases
3. Absolute zero unattainable

Key Equations

# Thermodynamic relationships
def gibbs_free_energy(H, S, T):
    """
    Determine spontaneity.
    G = H - TS
    """
    return H - T * S

def equilibrium_constant(dG):
    """
    Calculate K from ΔG°.
    ΔG° = -RT ln K
    """
    R = 8.314  # J/(mol·K)
    return np.exp(-dG / (R * 298))

def nernst_potential(E, Q, n):
    """
    Concentration effect on potential.
    E = E° - (RT/nF) ln Q
    """
    return E - (0.0592 / n) * np.log10(Q)

Kinetics

• Rate laws and order
• Activation energy (Arrhenius)
• Transition state theory
• Catalysis
• Reaction mechanisms

Quantum Chemistry

• Wave mechanics
• Schrödinger equation
• Molecular orbitals
• Born-Oppenheimer approximation
• Hartree-Fock theory
• Density functional theory

Spectroscopy

• UV-Vis: Electronic transitions
• IR: Vibrational transitions
• NMR: Nuclear spin transitions
• EPR: Electron spin transitions
• Raman: Vibrational (inelastic)