Approximate analytical gradients and nonadiabatic couplings for the state-average density matrix renormalization group self-consistent field method

Abstract

We present an approximate scheme for analytical gradients and nonadiabatic couplings for calculating state-average density matrix renormalization group self-consistent-field wavefunction. Our formalism follows closely the state-average complete active space self-consistent-field (SA-CASSCF) \emph{ansatz}, which employs a Lagrangian, and the corresponding Lagrange multipliers are obtained from a solution of the coupled-perturbed CASSCF (CP-CASSCF) equations. We introduce a definition of the matrix product state (MPS) Lagrange multipliers based on a single-site tensor in a mixed-canonical form of the MPS, such that a sweep procedure is avoided in the solution of the CP-CASSCF equations. We apply our implementation to the optimization of a conical intersection in 1,2-dioxetanone, where we are able to fully reproduce the SA-CASSCF result up to arbitrary accuracy.

arXiv comment17 pages, 3 figures, 2 tables

References in corpus (28)

• The density-matrix renormalization group in the age of matrix product states
• The density-matrix renormalization group
• Thermodynamic limit of the density matrix renormalization for the spin-1 Heisenberg chain
• Time-dependent variational principle for quantum lattices
• Ab Initio Quantum Chemistry using the Density Matrix Renormalization Group
• From density-matrix renormalization group to matrix product states
• The radical character of the acenes: A density matrix renormalization group study
• A class of ansatz wave functions for 1D spin systems and their relation to DMRG
• Orbital Optimization in the Density Matrix Renormalization Group, with applications to polyenes and β-carotene
• Low-energy spectrum of iron-sulfur clusters directly from many-particle quantum mechanics
• The density matrix renormalization group for ab initio quantum chemistry
• Measuring orbital interaction using quantum information theory
• Controlling the accuracy of the density matrix renormalization group method: The Dynamical Block State Selection approach
• Tangent-space methods for uniform matrix product states
• An Efficient Matrix Product Operator Representation of the Quantum-Chemical Hamiltonian
• Pushing Configuration-Interaction to the Limit: Towards Massively Parallel MCSCF Calculations
• A general second order complete active space self-consistent-field solver for large-scale systems
• New Approaches for ab initio Calculations of Molecules with Strong Electron Correlation
• QC-DMRG study of the ionic--neutral curve crossing of LiF
• Spin-adapted Matrix Product States and Operators
• Computation of extreme eigenvalues in higher dimensions using block tensor train format
• DMRG-SCF study of the singlet, triplet, and quintet states of oxo-Mn(Salen)
• Four-Component Density Matrix Renormalization Group
• Second-Order Self-Consistent-Field Density-Matrix Renormalization Group
• Linear Response Theory for the Density Matrix Renormalization Group: Efficient Algorithms for Strongly Correlated Excited States
• Analytic response theory for the density matrix renormalization group
• Excitation of Nucleobases from a Computational Perspective II: Dynamics
• The Thouless theorem for matrix product states and subsequent post-density matrix renormalization group methods

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