MOLPROP project - Results and Achievements
We describe below the scientific highlights from each of the nodes,
emphasizing the contracted work plan, the midterm milestones and
the collaborative aspects.
P1 KTH-Stockholm
The Stockholm partner has continued to focus
on the development and application of
response methodology for non-linear optical properties.
The research efforts devoted to various
optical limiting processes have given rich results, especially
concerning the the goal to
derive useful materials for laser protection.
In addition to the multi-dimensional
and multi-branched structures, reported on in the 1-year report,
we have now derived a series of metallo-porphyrines and
platinum containing compounds with outstanding
optical limiting properties.
A strong effort on the methodological development
paved the way for these results, in particluar
a non-linear density functional theory based on the quasi-energy
ansatz, including all
modern exchange-correlation functionals. This development also
concerned full and approximate
relativistic algorithms and effective core potentials,
and a dynamical, density matrix based, theory
for pulse propagation in multi-photon active media.
The main collaborators in this work are Oslo, Odense and Pisa nodes.
The research adheres mostly
to the second milestone of the mid-term review.
P2 U-Valencia This node has implemented the calculation
of SCF and MP2 energies from
Cholesky-decomposed two electron integrals.
The work on van der Waals complexes has continued
together with the Santiago node.
A new collaboration line has been
opened with the Stockholm YR using coupled cluster methods
together with ECP and Douglas-Kroll relativistic
methods for calculations of heavy metal compounds.
A joint project with the Modena node is started, focusing on
coupled cluster
studies of the polarizabilities and hyperpolarizabilities of benzene isomers.
In collaboration with the Mainz node, we determine the NMR spectra
of HCP and CH3CP at the coupled cluster level.
P3 U-Santiago de Compostela During the second year of the
network, this node continued working on the
development of a gauge-invariant coupled cluster model using the
time-dependent Lagrangian response approach and nonorthogonal orbital
rotations. Now we are dealing with the implementation of the model using
the Cholesky decomposition in order to reduce the scaling.
We work together with the nodes in Valencia and Odense.
The applications we carried out dealt with the evaluation of molecular
properties using the coupled cluster method and augmented correlation
consistent basis sets. We studied (hyper)polarizabilities,
second virial coefficients and intermolecular potential energy
surfaces and corresponding dynamics of the helium-, neon-, and
argon-molecule van der Waals complexes.
This work has been carried out together with the nodes
in Pisa, Aarhus, Valencia and Odense.
P4 U-Mainz At the node in Mainz, analytic second
derivatives for excitation
energies calculated at the CCSD linear response theory level are
currently implemented (by Dan Jonsson).
The nodes at Mainz and Pisa (A. Rizzo) developed a coupled-cluster
response theory approach for the determination of effective
quadrupole centers and applied this scheme to CO, OCS, and N2O.
In collaboration with the node in Valencia (with T.B. Pedersen),
the possibility to compute temperature effects on molecular properties
(e.g. NMR shieldings) has been implemented.
Together with the node in Valencia, highly accurate coupled-cluster
calculations for the
NMR spectrum (shieldings and coupling constants) of HCP have been carried out.
In collaboration with the node in Helsinki a program
for calculating current densities within the
gauge-including atomic-orbital framework
has been written and is now applied to investigate ring current effects.
Together with the nodes in Odense
and Oslo an extensive study concerning the accuracy of calculated
equilibrium geometries as well as the accuracy of
geometries derived from experimental rotation constants has been performed.
P5-Modena The analytic procedure of continuous transformation
of the origin of
the current density-diamagnetic term to zero for the
calculation of magnetic
susceptibility and nuclear magnetic shielding has been implemented within
the DALTON code.
This work is done in collaboration with the Odense node.
The graphical codes implemented in the first year of activity
have been used for representing
streamlines and modulus of the current density induced by a
magnetic field in the electrons of
a series molecules: 2- and 4-pyrones, 1-2 dithiin and
its derivatives, heteropentalenes and
s-indacene. The aromaticity of these systems has been
discussed in relation to magnetic properties.
This work is carried out jointly with the Valencia node.
Calculation of electric dipole polarizabilities in dipole velocity
and acceleration forms at the
coupled-cluster level is being carried out in collaboration with
the Oslo node.
A new efficient coupled Hartree-Fock computational scheme for parity-violating
energy differences in enantiomeric molecules, based on the density matrix formalism, has been developed.
P6 CNR-Pisa The work has concerned
studies of electric and magnetic, optical properties in molecules, in
collaborations with other nodes.
Study of interaction induced properties in neon using a Coupled Cluster
approach.
(Collaboration with the node of Santiago de Compostela).
Study of the effect of triple excitations on the Electric Field Gradient
induced birefringence
of polar molecules
(Collaboration with the node of Mainz).
Study of the Raman and Raman Optical activity spectra of Carbohydrates,
using Hartree Fock Response theory
(Involving the YR).
Study of the effect of relativity on the Raman Scattering of small
molecules
(Involving the YR).
Analysis of the behavior of Density Functional Theory employed for the study
of properties
at the nuclei (Nuclear potential, electric field and its gradient at the
nucleus, Sternheimer
shieldings and polarizabilities of the EFG at the nucleus
(Collaboration with the nodes of Oslo and Stockholm).
P7 U.Helsinki The MOLPROP collaboration between the
Helsinki node and the Arhus group
of the Odense node has focused on development of computational
approaches for calculation of optical and dynamical properties of
strain-induced quantum dots. The methods are being implemented into
a new ab initio program package. A main goal is to
find a quantum dot system with such a size and
shape for which the recombination dipole moment is large but the
lines are still narrow enough for identifying individual transitions.
The present methods have successfully been used for studying
nanotechnologically important semiconductor quantum dots containing
electrons and holes. The collaboration with the Odense group of the Odense
node consists mainly of investigations of optical properties of
Bi compounds using their relativistic 4-component RPA method.
The collaboration with the
Mainz node involves the development of a computational method to
calculate the magnetically induced current density employing
gauge-including atomic orbitals.
P8 U.Odense Calculation of frequency
dependent polarizabilities using the coupled cluster
approximate triples model (CC3) has been implemented with reduced scaling.
We have demonstrated that most accurate equilibrium geometries are
obtained based on experimental vibration ground state constants and
calculated vibration-rotation interaction constants.
A new large-scale CI module has been incorporated in the relativistic
four-component second-order MCSCF program.
Theory for a more correct account for the
free particle g-factor in EPR has been
implemented in the relativistic EPR program.
Theory and implementation for MCSCF calculations of near-resonant absorption
with account for finite lifetimes has been finished.
QM/MM methods have been developed and implemented at the Hartree-Fock, MCSCF
and Coupled Cluster levels.
These methods enable calculations of properties up to third order.
Heterogeneous solvation models have been developed and implemented at the
Hartree-Fock and MCSCF levels
and these methods enable calculations of properties up to fourth order.
P9 U-Oslo The Oslo node has worked on the implementation
of multipole methods
in Dalton. A fully working, efficient implementation of the tree-code
algorithm is now in place (scales as NLogN), and some optimization
is being carried out on the fast multipole method (scales as N).
Test calculations on systems containing several hundred atoms show
that the classical contribution to the Coulomb energy can now
be calculated very efficiently.
In collaboration with the Stockholm node, quadratic response has
been implemented at the LDA, GGA, and hybrid DFT levels of theory.
In collaboration with the Aarhus node, very accurate calculations
have been carried out molecular structure and vibrational energy
levels, yielding important information about the performance of
ab initio models.
In collaboration with the Modena node, work is being carried out
on the calculation of polarizabilities in different gauges.
Theoretical Chemistry,
MOLPROP
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