What is QMAS (Quantum MAterials Simulator)

QMAS is an ab initio electronic-structure computational code package based on the projector augmented-wave (PAW) with plane wave basis set. It consist of three subprogram packages “qmas_atom” and “qmas_band”.

The purposes of the QMAS development are:

• To provide a platform to maintain and increase our ability to develop (plane-waved-based) codes by sharing knowledge, know-how and culture concerning computational physics.
  
• To provide a platform incorporate new techniques or methods developed by ourselves or someone else.
• To provide an efficient tool to solve practical problems in between solid state physics and materials science.

Specifications of QMAS are as follows:

• Total energy and forces by periodic cell
• Local density approximation (LDA, LSDA: PZ-CA) and generalized gradient approximation (GGA: PBE96)
• PAW pseudopotentials developed by qmas_atom
• All space groups (#1 - #230) are available by TSPACE* and SYMSPACE**
• Kerker and Pulay type charge mixing schemes
• All-band Davidson and Kosugi-algorism solvers to update wave functions
• Lattice and atomic structure optimization by cell stress and atomic force supported by TSPACE and SYMSPACE
• Charge extrapolation by Arias and Alfe scheme
• LDA+U and GGA+U methods by Dudarev (Ueff = U-J) and Liechtenstein (U and J) version
• Berry's phase calculation
• Wannier function
• Applying electric field with the saw-tooth scheme and by Souza version
• Optical conductivity
• Analysis of wave functions, charge and spin densities
• Analysis of Mulliken population
• Total density of states (TDOS), local DOS (LDOS) and projected DOS (PDOS)
• Analysis of energy and stress densities
• Flexible format of input data
• dynamic memory allocation
• K-point loop or band loop Parallelization by Message Passing Interface (MPI)
  
  * TSPACE is a program for space group developed by Prof. A. Yanase.
  ** SYMSPACE is an interface program between TSPACE and QMAS.
  

The current developing team consists of the following members:

• Shoji ISHIBASHI (RICS-AIST)
  
• Tomoyuki TAMURA (RICS-AIST)
  
• Shingo TANAKA (UBIQUEN-AIST)
  
• Masanori KOHYAMA (UBIQUEN-AIST)
  
• Kiyoyuki TERAKURA (JAIST).

There are significant contributions from

• Guang-Yu GUO (NTU)
  
• Ming-Hsien LEE (TKU)
  
• Taisuke OZAKI (JAIST)
  
• Sheng-Feng HUANG (RICS-AIST)
  
• Hongming WENG (JAIST)
  
• Nozomi ORITA (RICS-AIST)