Changes in default settings:
Single-node shared-memory parallelism becomes default and recommended for most jobs. New command line key -mpi is required to use distributed-memory MPI-parallel features (Section 2.8).
Pure basis functions are used by default with BASIS = GEN.
Default number of grid points in Lebedev grids in solvent models changed from 302 to 194 points (non-Hydrogen) and 110 points (Hydrogen) atoms.
Use of SWIG charges for SMx models.
Input format for XPol, SAPT and XSAPT, and MBE jobs has changed.
Use EDA2 as the default driver for ALMO-EDA.
Frozen core approximation no longer applied by default in RAS-CI calculations.
Increased availability of basis sets: High angular momentum basis functions (up to k-functions) supported for most SCF, RI-MP2, CC, EOM-CC, ADC calculations.
Streamlined input format for RI-SCF calculations.
Added the def2- family of density fitted (RI) basis sets for SCF and post-SCF calculations (courtesy of Dr. Florian Weigend).
On-the-fly generation for the superposition of atomic densities guess for SCF (Kevin Carter-Fenk, John Herbert).
Reintroduction of legacy ECPs without fitting.
Easy specification of basis sets on fragments, reading of basis sets from an external file (Zheng Pei and Yihan Shao).
Improvements to the DFT capabilities:
Support for analytic frequency calculations using meta-GGA density functionals (available only with shared-memory parallelism).
Support for analytic frequency calculations using resolution-of-the-identity (density-fitted) Coulomb (available only with shared-memory parallelism).
Improved performance of analytic partial Hessian calculations using DFT.
New density functionals: revM06, revM11 (Pierpaolo Morgante and Roberto Peverati).
Improvements in implicit solvation models:
Revised PCM tessellation grids for improved performance (John Herbert).
Improved performance of the general SCF program with SM solvation models (Yuezhi Mao).
New MP2 features:
Addition of regularized orbital-optimized second-order Møller-Plesset perturbation theory (-OOMP2) (Joonho Lee, Martin Head-Gordon; Section 6.6.6).
Enhancements to the coupled-cluster package:
Damped response, dynamic polarizabilities for two-electron absorption using EOM-CC (Kaushik Nanda and Anna Krylov).
Better handling of linear point groups in ADC and CC methods.
Improved performance of disk-based ADC/CC algorithms.
Projected and Voronoi CAP for CAP-EOM-CC/CC calculations (Ksenia Bravaya, Alexander Kunitsa; Section 7.10.9).
Dynamic polarizabilities for CCSD and EOM-CCSD (Kaushik Nanda, Anna Krylov; Section 22.214.171.124).
Improved evaluation of spin-orbit coupling constants using EOM-CC wavefunctions (Pavel Pokhilko and Anna Krylov).
New features for SOC calculation and analysis (Pavel Pokhilko, Anna Krylov; Section 126.96.36.199).
Dyson orbitals for CVS-EOM-CCSD (Marta Vidal, Sonia Coriani, Anna Krylov; Section 7.10.8).
Improvements in energy decomposition analysis methods:
Added electron density difference (EDD) plots and the ETS-NOCV analysis (Yuezhi Mao).
Added support for PCM and SMD solvation models in ALMO-EDA (Yuezhi Mao).
Resolved several issues that caused instabilities in MP2-EDA calculations (Yuezhi Mao).
New capabilities for explicit solvation modeling:
Polarizable Embedding (PE) Model for ground-state and ADC calculations (Maximilian Scheurer; Section 11.8).
Other new methods and capabilities:
Incremental FCI method (Paul Zimmerman).
Transition potential DFT for core-valence excitations.
Analytic evaluation of Raman intensities (Zheng Pei and Yihan Shao).