WIEN2k is an APW+lo program for calculating the properties of solids. It is based on the augmented plane wave plus local orbitals (APW+lo) method, which considers all electrons (core and valence) self-consistently in a full-potential treatment. The APW+lo method is implemented efficiently in WIEN2k, with various types of parallelization and optimized numerical libraries. The program can calculate a wide range of properties, from basic ones like the electronic band structure to more specialized ones like the nuclear magnetic resonance shielding tensor or the electric polarization. The APW+lo method is a computational approach that uses a combination of plane waves and local orbitals to describe the electronic structure of solids. It is particularly effective for systems with complex electronic structures, such as those involving transition metals and f-elements. The method involves decomposing the unit cell into spheres centered at the nuclear sites and an interstitial region, and using a combination of plane waves and local orbitals to describe the electronic structure. The program is capable of calculating various properties of solids, including the electronic band structure, the optimized atomic structure, and the nuclear magnetic resonance shielding tensor. It also supports the use of different exchange-correlation functionals, including local density approximation (LDA), generalized gradient approximation (GGA), and meta-GGA. The program is also capable of calculating the bandgap of solids, which is a critical property for understanding the electronic behavior of materials. The APW+lo method is particularly effective for systems with complex electronic structures, such as those involving transition metals and f-elements. The method involves decomposing the unit cell into spheres centered at the nuclear sites and an interstitial region, and using a combination of plane waves and local orbitals to describe the electronic structure. The program is capable of calculating various properties of solids, including the electronic band structure, the optimized atomic structure, and the nuclear magnetic resonance shielding tensor. It also supports the use of different exchange-correlation functionals, including local density approximation (LDA), generalized gradient approximation (GGA), and meta-GGA. The program is also capable of calculating the bandgap of solids, which is a critical property for understanding the electronic behavior of materials.WIEN2k is an APW+lo program for calculating the properties of solids. It is based on the augmented plane wave plus local orbitals (APW+lo) method, which considers all electrons (core and valence) self-consistently in a full-potential treatment. The APW+lo method is implemented efficiently in WIEN2k, with various types of parallelization and optimized numerical libraries. The program can calculate a wide range of properties, from basic ones like the electronic band structure to more specialized ones like the nuclear magnetic resonance shielding tensor or the electric polarization. The APW+lo method is a computational approach that uses a combination of plane waves and local orbitals to describe the electronic structure of solids. It is particularly effective for systems with complex electronic structures, such as those involving transition metals and f-elements. The method involves decomposing the unit cell into spheres centered at the nuclear sites and an interstitial region, and using a combination of plane waves and local orbitals to describe the electronic structure. The program is capable of calculating various properties of solids, including the electronic band structure, the optimized atomic structure, and the nuclear magnetic resonance shielding tensor. It also supports the use of different exchange-correlation functionals, including local density approximation (LDA), generalized gradient approximation (GGA), and meta-GGA. The program is also capable of calculating the bandgap of solids, which is a critical property for understanding the electronic behavior of materials. The APW+lo method is particularly effective for systems with complex electronic structures, such as those involving transition metals and f-elements. The method involves decomposing the unit cell into spheres centered at the nuclear sites and an interstitial region, and using a combination of plane waves and local orbitals to describe the electronic structure. The program is capable of calculating various properties of solids, including the electronic band structure, the optimized atomic structure, and the nuclear magnetic resonance shielding tensor. It also supports the use of different exchange-correlation functionals, including local density approximation (LDA), generalized gradient approximation (GGA), and meta-GGA. The program is also capable of calculating the bandgap of solids, which is a critical property for understanding the electronic behavior of materials.