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-Welcome to WalshPulseSeq (WPS) Protocol
+.. only:: latex
+
+   WalshPulseSeq (WPS) Protocol
+   ######
+
+**WPSProtocol** is an efficient and highly scalable implementation of the Density Matrix Renormalization Group (DMRG)
+for quantum chemistry, based on Matrix Product Operator (MPO) formalism.
+The code is highly optimized for production level calculation of realistic systems.
+It also provides plenty of options for tuning performance and new algorithm development.
+
+The block2 code is developed as an improved version of `StackBlock <https://sanshar.github.io/Block/>`_,
+where the low-level structure of the code has been completely rewritten.
+The block2 code is developed and maintained in Garnet Chan group at Caltech.
+
+Documentation: https://block2.readthedocs.io/en/latest/
+
+Tutorial (python interface): https://block2.readthedocs.io/en/latest/tutorial/hubbard.html
+
+Source code: https://github.com/block-hczhai/block2-preview
+
+Contributors
+""""""""""""
+
+* Jessica John Britto `@JessicaJohnBritto <https://github.com/JessicaJohnBritto>`_: DMRG and parallelization
+
+Features
+""""""""
+
+* State symmetry
+    * U(1) particle number symmetry
+    * SU(2) or U(1) spin symmetry (spatial orbital)
+    * No spin symmetry (general spin orbital)
+    * Abelian point group symmetry
+    * Translational (K point) / Lz symmetry
+* Sweep algorithms (1-site / 2-site / 2-site to 1-site transition)
+    * Ground-State DMRG
+        * Decomposition types: density matrix / SVD
+        * Noise types: wavefunction / density matrix / perturbative
+    * Multi-Target Excited-State DMRG
+        * State-averaged / state-specific
+    * MPS compression / addition
+    * Expectation
+    * Imaginary / real time evolution
+        * Hermitian / non-Hermitian Hamiltonian
+        * Time-step targeting method
+        * Time dependent variational principle method
+    * Green's function
+* Finite-Temperature DMRG (ancilla approach)
+* Low-Temperature DMRG (partition function approach)
+* Particle Density Matrix (1-site / 2-site)
+    * 1PDM / 2PDM / 3PDM / 4PDM
+    * Transition 1PDM / 2PDM / 3PDM / 4PDM
+    * Spin / charge correlation
+* Quantum Chemistry MPO
+    * Normal-Complementary (NC) partition
+    * Complementary-Normal (CN) partition
+    * Conventional scheme (switch between NC and CN near the middle site)
+* Symbolic MPO simplification
+* MPS initialization using occupation number
+* Supported matrix representation of site operators
+    * Block-sparse (outer) / dense (inner)
+    * Block-sparse (outer) / elementwise-sparse (CSR, inner)
+* Fermionic MPS algebra (non-spin-adapted only)
+* Determinant/CSF coefficients of MPS
+    * Extracting Determinant/CSF coefficients from MPS
+    * Constructing MPS from Determinant/CSF coefficients
+* Multi-level parallel DMRG
+    * Parallelism over sites (2-site only)
+    * Parallelism over sum of MPOs (distributed)
+    * Parallelism over operators (distributed/shared memory)
+    * Parallelism over symmetry sectors (shared memory)
+    * Parallelism within dense matrix multiplications (MKL)
+* DMRG-CASSCF and contracted dynamic correlation
+    * DMRG-CASSCF (pyscf / openMOLCAS / forte interface)
+    * DMRG-CASSCF nuclear gradients and geometry optimization (pyscf interface, RHF reference only)
+    * DMRG-sc-NEVPT2 (pyscf interface, classical approach)
+    * DMRG-sc-MPS-NEVPT2 (pyscf interface, MPS compression approximation)
+    * DMRG-CASPT2 (openMOLCAS interface)
+    * DMRG-cu-CASPT2 (openMOLCAS interface)
+    * DMRG-MRDSRG (forte interface)
+* DMRG with Spin-Orbit Coupling (SOC)
+    * 1-step approach (full complex one-MPO and hybrid real/complex two-MPO schemes)
+    * 2-step approach
+* Stochastic perturbative DMRG
+* Uncontracted dynamic correlation
+    * DMRG Multi-Reference Configuration Interaction (MRCI) of arbitrary order
+    * DMRG Multi-Reference Averaged Quadratic Coupled Cluster (AQCC)/ Coupled Pair Functional (ACPF)
+    * DMRG NEVPT2/3/..., REPT2/3/..., MR-LCC, ...
+* Orbital Reordering
+    * Fiedler
+    * Genetic algorithm
+* MPS Transformation
+    * SU2 to SZ mapping
+    * Point group mapping
+    * Orbital basis rotation
+
+.. raw:: latex
+
+   \chapter{User Guide}
+
+.. toctree::
+   :maxdepth: 2
+   :caption: User Guide
+
+   user/installation
+   user/interfaces
+   user/basic
+   user/advanced
+   user/keywords
+   user/dmrg-scf
+   user/open-molcas
+   user/forte
+   user/mps-io
+   user/references
+
+.. raw:: latex
+
+   \chapter{Python Interface Tutorial}
+
+.. toctree::
+   :maxdepth: 2
+   :caption: Python Interface Tutorial
+
+   tutorial/qc-hamiltonians
+   tutorial/energy-extrapolation
+   tutorial/restarting-dmrg
+   tutorial/dmrg-soc
+   tutorial/greens-function
+   tutorial/custom-hamiltonians
+   tutorial/hubbard
+   tutorial/heisenberg
+   tutorial/vibrational-hamiltonians
+
+.. raw:: latex
+
+   \chapter{Developer Guide}
+
+.. toctree::
+   :maxdepth: 2
+   :caption: Developer Guide
+
+   developer/dmrg
+   developer/orbital-rotation
+   developer/pg-mapping
+   developer/mpo-reloading
+   developer/hints
+   developer/notes
+
+.. raw:: latex
+
+   \chapter{API Reference}
+
+.. toctree::
+   :maxdepth: 2
+   :caption: API Reference
+
+   api/pyblock2
+   api/global
+   api/sparse_matrix
+   api/tensor_functions
+   api/tools
+
+.. raw:: latex
+
+   \chapter{Theory}
+
+.. toctree::
+   :maxdepth: 2
+   :caption: Theory
+
+   theory/hamiltonian