sigma_ppm_uks.h

Go to the documentation of this file.

/*
 *            Copyright 2009-2020 The VOTCA Development Team
 *                       (http://www.votca.org)
 *
 *      Licensed under the Apache License, Version 2.0 (the "License")
 *
 * You may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *              http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 */
 
#pragma once
#ifndef VOTCA_XTP_SIGMA_PPM_UKS_H
#define VOTCA_XTP_SIGMA_PPM_UKS_H
 
#include "votca/xtp/ppm.h"
#include "votca/xtp/sigma_base_uks.h"
 
namespace votca {
namespace xtp {
 
class Sigma_PPM_UKS : public Sigma_base_UKS {
 public:
  Sigma_PPM_UKS(TCMatrix_gwbse_spin& Mmn, RPA_UKS& rpa,
                TCMatrix::SpinChannel spin)
      : Sigma_base_UKS(Mmn, rpa, spin) {}
 
  void SetSharedPPM(const PPM& ppm) { ppm_ = &ppm; }
 
  void PrepareScreening() final;
 
  double CalcCorrelationDiagElement(Index gw_level,
                                    double frequency) const final;
 
  double CalcCorrelationDiagElementDerivative(Index gw_level,
                                              double frequency) const final;
 
  // All frequencies in one pass (far poles via Chebyshev interpolation, see
  // exact_pole_sums)
  Eigen::VectorXd CalcCorrelationDiagElements(
      Index gw_level, const Eigen::VectorXd& frequencies) const final;
 
  double CalcCorrelationOffDiagElement(Index gw_level1, Index gw_level2,
                                       double frequency1,
                                       double frequency2) const final;
 
 private:
  template <class Term>
  double AccumulateDiag(Index gw_level, double frequency, Term term) const;
  const PPM* ppm_ = nullptr;
  // per PPM mode: 0.5 weight omega, 0 for weights below 1e-9 (see
  // Sigma_PPM; set in PrepareScreening)
  Eigen::VectorXd mode_factors_;
};
 
}  // namespace xtp
}  // namespace votca
 
#endif