inorganic-chemistry

# Inorganic Chemistry ## What I Do I provide comprehensive inorganic chemistry tools including coordination chemistry, organometallic compounds, crystal field theory, transition metal complexes, and spectroscopic analysis for chemistry applications. ## When to Use Me - Coordination compound analysis - Crystal field splitting calculations - Organometallic reaction mechanisms - Transition metal spectroscopy - Ligand field theory - Inorganic synthesis planning ## Core Concepts - **Coordination Chemistry**: Ligands, coordination numbers - **Crystal Field Theory**: d-orbital splitting, CFSE - **Ligand Field Theory**: Molecular orbital approach - **Organometallic Chemistry**: Metal-carbon bonds - **Spectroscopy**: UV-Vis, IR, NMR, EPR - **Redox Chemistry**: Oxidation states, potentials - **Solid State**: Defects, non-stoichiometry - **Bioinorganic**: Metalloenzymes, metals in biology ## Code Examples ### Coordination Chemistry ```python from itertools import permutations LIGAND_TYPES = { 'monodentate': 1, 'bidentate': 2, 'tridentate': 3, 'tetradentate': 4, 'hexadentate': 6 } GEOMETRIES = { 2: 'linear', 3: 'trigonal planar', 4: 'tetrahedral/square planar', 5: 'trigonal bipyramidal/square pyramidal', 6: 'octahedral', 8: 'square antiprismatic' } def coordination_number(metal, ligands): return sum(LIGAND_TYPES.get(ligand, 1) for ligand in ligands) def effective_atomic_number(metal_z, oxidation_state, ligands): metal_e = metal_z - oxidation_state ligand_e = sum(18 if l in ['CO', 'CN-', 'NO+'] else 2 for l in ligands) return metal_e + ligand_e def igeometry(coordination_number, metal_electron_config): if coordination_number == 4: d_count = metal_electron_config.get('d_electrons', 0) if d_count < 8: return 'tetrahedral' else: return 'square planar' return GEOMETRIES.get(coordination_number, 'unknown') def ionization_isomerism(metal, ligands, counter_ions): return len(list(permutations(counter_ions))) def hydrate_isomerism(metal, ligands, water_positions): return water_positions coordination_number = coordination_number('Fe', ['H2O', 'H2O', 'CN-', 'CN-', 'CN-', 'CN-']) print(f"Coordination number: {coordination_number}") EAN = effective_atomic_number(26, 2, ['CO', 'CO', 'CO', 'CO']) print(f"Effective atomic number: {EAN}") ``` ### Crystal Field Theory ```python import numpy as np def cfse_oh(d_electrons, spin_state, delta_oct): high_spin = { 0: 0, 1: 0, 2: 0, 3: -0.4*delta_oct, 4: -0.8*delta_oct, 5: -1.2*delta_oct, 6: -1.6*delta_oct + P, 7: -2.0*delta_oct + P, 8: -2.4*delta_oct + 2*P, 9: -1.8*delta_oct + 2*P, 10: -2.4*delta_oct + 2*P } low_spin = { 0: 0, 1: -0.4*delta_oct, 2: -0.8*delta_oct, 3: -1.2*delta_oct, 4: -1.6*delta_oct, 5: -2.0*delta_oct, 6: -2.4*delta_oct, 7: -2.8*delta_oct, 8: -3.2*delta_oct, 9: -3.6*delta_oct + 2.5*P, 10: -4.0*delta_oct + 2.5*P } if spin_state == 'high': return high_spin.get(d_electrons, 0) return low_spin.get(d_electrons, 0) def tanabe_sugano_diagram(d_electron): diagrams = { 'd1': 'Ground state: 2T2g', 'd2': 'Ground state: 3T1g', 'd3': 'Ground state: 4A2g', 'd5_high': 'Ground state: 6A 'd61g', _low': 'Ground state: 1A1g' } return diagrams.get(f'd{d_electron}', 'Consult diagram') def magnetic_moment(spin_only, spin_quantum): return np.sqrt(spin_quantum * (spin_quantum + 2)) def orbital_contribution_L(L): return np.sqrt(L * (L + 1)) def racah_parameter(A, B, C): return A - B, B, C delta_oct = 15000 # cm^-1 d6_cfse = cfse_oh(6, 'low', delta_oct) print(f"CFSE for low-spin d6: {d6_cfse:.0f} cm^-1") spin_only = 2 # S = 2 mu_so = magnetic_moment(True, spin_only) print(f"Spin-only magnetic moment: {mu_so:.1f} BM") ``` ### Ligand Field Theory ```python def ligand_field_splitting(ligand_series): spectrochemical_series = ['I-', 'Br-', 'Cl-', 'F-', 'OH-', 'H2O', 'NH3', 'en', 'NO2-', 'CN-', 'CO'] return ligand_series in spectrochemical_series def nephelauxetic_effect(beta): return beta # B_free / B_complex def mixing_coefficient(d_electrons, ligands): return 0.1 * d_electrons * len(ligands) def molecular_orbital_diagram(metal, ligands, symmetry): return {'sigma': [], 'pi': [], 'delta': []} def backbonding_strength(metal_d_electrons, pi_acceptor_ligands): return metal_d_electrons * len(pi_acceptor_ligands) / 2 def covalency_parameter(h): return 1 - h # h = (beta_free - beta) / beta_free def charge_transfer_energy(metal_oxidation, ligand_donation, pi_backbonding): return metal_oxidation - ligand_donation + pi_backbonding ``` ### Organometallic Chemistry ```python def electron_counting_ionic(metal_ox, metal_group, ligands): return metal_group - metal_ox + sum(ligand_hapticity(lig) for lig in ligands) def electron_counting_covalent(metal_group, ligands): return metal_group + sum(ligand_hapticity(lig) for lig in ligands) def ligand_hapticity(eta_n): return n def effective_atomic_number_rule(electron_count): return 18 # Noble gas configuration def stability_18_electron_rule(total_electrons): if total_electrons == 18: return 'Stable 18-electron complex' elif total_electrons < 18: return f' electron-deficient: {18 - total_electrons} electrons needed' return f' electron-rich: {total_electrons - 18} electrons extra' def catalytic_cycle_step(oxidative_addition, rate_constant): if oxidative_addition: return 'OA - increase oxidation state by 2' return 'RE - reductive elimination' electron_count = electron_counting_covalent(8, ['CO', 'CO', 'CO', 'CO', 'H']) print(f"Electron count: {electron_count}") stability = stability_18_electron_rule(18) print(stability) ``` ### Inorganic Spectroscopy ```python def d_d_transition_energy(CFSE, pairing_energy): return CFSE + pairing_energy def selection_rules(delta_l, delta_s, parity): return delta_l == 1 and delta_s == 0 and parity == 'odd' def extinction_coepsilon(epsilon_max, bandwidth): return epsilon_max * bandwidth def ir_stretching_frequency(bond_order, reduced_mass): return 1/(2*np.pi) * np.sqrt(k / reduced_mass) def epr_g_value(h_nu, beta_e, D): return (h_nu - D) / (beta_e * B) def nmr_chemical_shift(reference, sample): return (nu_sample - nu_reference) / nu_reference * 1e6 def mossbauer_isomer_shift(electron_density): return electron_density nu_ref = 100.0 nu_sample = 100.5 shift = nmr_chemical_shift(nu_ref, nu_sample) print(f"Chemical shift: {shift:.1f} ppm") ``` ## Best Practices 1. **Oxidation States**: Assign carefully 2. **Spectroscopic Assignment**: Consider all transitions 3. **Magnetic Properties**: Measure experimentally 4. **Kinetics**: Consider substitution mechanisms 5. **Bonding**: Use appropriate model ## Common Patterns ```python # Walsh diagrams def walsh_diagram_correlations(): pass # Covalent bond classification def covalent_classification(): pass ``` ## Core Competencies 1. Coordination chemistry 2. Crystal field theory 3. Organometallic chemistry 4. Inorganic spectroscopy 5. Structure-property relationships