51) S. Keller, M. Dolfi, M. Troyer, M. Reiher
An Efficient Matrix Product Operator Representation of the Quantum-Chemical Hamiltonian
J. Chem. Phys. 143 2015, 244118 [arXiv: 1510.02026]
This paper describes the first second-generation, i.e., matrix-product-operator based DMRG program for the quantum chemical Hamiltonian with full Coulomb interaction that is as efficient as the most efficient first-generation codes. The advantages of this second-generation algorithm are its site-specific matrix-product operators and its easy implementation of expectation values of any kind.
50) M. Bergeler, G. N. Simm, J. Proppe, M. Reiher
Heuristics-Guided Exploration of Reaction Mechanisms
J. Chem. Theory Comput. 11 2015, 5712-5722
In this paper, we present a fully automated scheme for the exploration of reaction mechanisms. Reactive complexes are constructed based on heuristic principles. These principles derive from first-principles calculations, which makes our approach context independent. Stable intermediates of an emerging reaction networt are then optimized. Elementary reactions in this network are automatically proposed and connecting transition states automatically searched. The huge amounts of data produced are pruned by algorithms that eventually also produce graphical representations of the network generated. We demonstrated the power and elegance of our approach at the example of Schrock dinitrogen fixation catalysis, for which we generated about 10000 intermediates and a couple of hundred transition states. The full complexity of such a catalytic process was mapped onto a reaction network that visualized all essential features in an automated manner.
49) E. D. Hedegard, S. Knecht, J. S. Kielberg, H. J. Aa. Jensen, and M. Reiher
Density matrix renormalization group with efficient dynamical electron correlation through range separation
J. Chem. Phys. 142 2015, 224108
Whereas DMRG allows for much larger active orbital spaces than conventional CASSCF, its advantages vanish when combined with a mandatory post-DMRG dynamic-correlation treatment through multireference perturbation theory. Here, we showed how short-range DFT can efficiently account for dynamic correlation so that all computational advantages of DMRG can be preserved.
48) A. R. Finkelmann, M. T. Stiebritz, M. Reiher
Inaccessibility of the mu-hydride species in [FeFe] hydrogenases
Chem. Sci. 5 2014, 215–221
A mu-bridging hydride in biomimetic diiron clusters and active-site models of [FeFe] hydrogenases was known to be a thermodynamic sink of a hydrogen-production catalytic cycle. In this paper, we demonstrated how the amino acid environment in the protein prevents this species to be formed because of significant activation barriers which make the mu-H species kinetically inaccessible.
47) S. Knecht, O. Legeza, M. Reiher
Four-Component Density Matrix Renormalization Group (PDF, 463 KB)
J. Chem. Phys. 140 2014, 041101
Here, we presented the first four-component implementation of the DMRG algorithm.
46) T. Weymuth, M. Reiher
Inverse Quantum Chemistry: Concepts and Strategies for Rational Compound Design
Int. J. Quantum Chem. 114 2014, 823-837
The desire to propose molecular structures with pre-defined function is counteracted in quantum mechanics by the fact that the electronic energy, from which all properties of a molecular system are derived, is obtained as an expectation value for a given structure that integrates out all dynamical degrees of freedom. As a consequence, the inverse direction from function to structure is not well defined. In this work, we review existing inverse approaches - including our own developments (mode-tracking, intensity-tracking, and gradient-driven molecule construction).
45) T. Weymuth, E. P. A. Couzijn, P. Chen, M. Reiher
New Benchmark Set of Transition-Metal Coordination Reactions for the Assessment of Density Functionals
J. Chem. Theory Comput. 10 2014, 3092–3103
Accurate reference data for reactions involving large transition metal complexes are very difficult to obtain. In this work, we presented the WCCR10 benchmark set of 10 ligand binding energies which proved to be a tough test case for modern density functional theory. This reference set clearly shows that not one contemporary density functional can be singled out for its superior performance. As a matter of fact, the accuracy of present-day functionals is, at times, not at all satisfactory and varies significantly with the system under study.
44) M. P. Haag, A. C. Vaucher, M. Bosson, S. Redon, M. Reiher
Interactive Chemical Reactivity Exploration
ChemPhysChem, 15 2014, 3301–3319
In this paper, we introduced the first interactive chemical reactivity exploration approach based on real-time quantum chemical calculations. The operator can conveniently explore potential energy hypersurfaces and experience the quantum mechanical forces exerted on the atoms of the molecular system with a haptic force-feedback device.
43) A. R. Finkelmann, H. M. Senn, M. Reiher
Hydrogen-Activation Mechanism of [Fe]-Hydrogenase Revealed by Multi-Scale Modeling
Chem. Sci. 5 2014, 4474–4482
This is the first study of a complete structural model of mono-iron hydrogenase, which demonstrated that small active-site models are not able to reproduce all structural effects. In fact, a hydride complex is not formed in the large QM/MM model. Moreover, dihydrogen activation by this enzyme features close similarities to H2 dissociation by frustrated Lewis pairs.
42) M. P. Haag, M. Reiher
Real-time Quantum Chemistry
Int. J. Quantum Chem. 113 2013, 8-20
Recent advances in quantum chemistry allow for a new view on quantum chemical calculations: If set up properly, it is possible to conduct them in real time and hence to work with their results instantaneously. Such a massive and direct flow of quantum chemical data will have consequences on how and what data shall be reported in computational chemistry papers.
41) K. Boguslawski, C. R. Jacob, M. Reiher
Optimized unrestricted Kohn–Sham potentials from ab initio spin densities
J. Chem. Phys. 138 2013, 044111
Potentials derived from energy density functionals via functional derivatives determine the accuracy of Kohn-Sham DFT calculations. To improve on existing ones, spin-state-dependent potentials should be constructed (Int. J. Quantum Chem. 112 (2012) 3661). Here, we reverse-engineered the potential from an accurate ab initio reference spin density in order to understand deficiencies in potentials derived from contemporary density functionals.
40) A. R. Finkelmann, M. T. Stiebritz, M. Reiher
Electric-Field Effects on the [FeFe]-Hydrogenase Active Site
ChemComm 49 2013, 8099
Electric fields exerted on a catalytic center - for instance, an active site in a metalloprotein that is in close contact with an electrode - can and will have an effect on the chemical reactivity of that center. These situations are, however, difficult to model. We proposed a Poisson-Boltzmann-based approach to derive a reasonable model electric field (accurate w.r.t. strength and direction) with which the electric-field modulation of a reaction mechanism can be assessed and rationalized.
39) K. Boguslawski, P. Tecmer, O. Legeza, M. Reiher
Entanglement Measures for Single- and Multi-Reference Correlation Effects
J. Phys. Chem. Letters 3 2012, 3129
Entropy-based entanglement measures from quantum information theory can be exploited to analyze electron correlation in active orbital spaces. We showed that they pave the way to automated active-space selection. These entropy measures also complement chemical bonding analysis (see J. Chem. Theory Comput. 9 (2013) 2959).
38) E. Mátyus, M. Reiher
Molecular structure calculations: a unified quantum mechanical description of electrons and nuclei using Gaussian functions and the global vector representation (PDF, 784 KB)
J. Chem. Phys. 137 2012, 024104
This work elaborates on a molecular structure theory that does not postulate molecular structure (as introduced by the Born-Oppenheimer approximation). As a consequence, it make no assumption on the properties of the particles that constitute a molecule (e.g., heavy nuclei vs. light electrons) and, in particular, avoids the Born-Oppenheimer approximation.
37) D. Peng, M. Reiher
Local Relativistic Exact Decoupling (PDF, 1 MB)
J. Chem. Phys. 136 2012 244108
Relativistic unitary transformation techniques like X2C, BSS, and DKH are computationally demanding for large molecules as one cannot afford to perform all matrix operators in the full primitive atomic-orbital basis. Hence, a local approach is required and some had already been proposed. Here, we introduce a consistent framework for all such approaches applied in the context of all unitary transformation techniques that have been successfully applied in relativistic quantum chemistry. We found a universal local approximation called DLU to the unitary matrix transformation.
36) D. Peng, M. Reiher
Exact Decoupling of the Relativistic Fock Operator (PDF, 402 KB)
Theor. Chem. Acc. 131 2012,1081
This review discusses all exact-decoupling approaches and presents the first direct numerical comparison of them. It highlights the computational cost of X2C, BSS, and DKH calculations. In fact, up to 8th order DKH calculations are more efficient than X2C and BSS calculations.
35) C. R. Jacob, M. Reiher
Spin in Density-Functional Theory
Int. J. Quantum Chem. 112 2012 3661-3684
Much gray and phenomenological knowledge is available on how to formulate a spin-resolved density functional theory. However, no complete and consistent presentation had been published. We closed this gap and embedded the nonrelativistic formulation into a relativistic framework. As a result, we could clearly identify promising future directions for dusty functional development.
34) K. Boguslawski, K. H. Marti, Ö. Legeza, M. Reiher
Accurate ab initio spin densities (PDF, 4 MB)
J. Chem. Theory Comput. 8 2012, 1970-1982
For a decade, it was discussed what density functionals might provide reasonable spin state energetics, it then turned out that even if some density functional is found to be sufficiently reliable for a certain system, the spin density might not be reasonable (see J. Chem. Theory Comput. 7 (2011) 2740). However, this does not come as a surprise considering the fact that calculating the correct value of an integral such as the energy expectation value correct does not imply that an underlying spin density disitribution is correct. However, the question is: what is the correct spin density in critical cases such as Fe nitrosyl complexes. We solved this problem by introducing DMRG spin density distributions for large active orbital spaces that allowed us to obtain spin densities converged with respect to the size of the active space.
33) E. Mátyus, J. Hutter, U. Müller-Herold, M. Reiher
Extracting elements of molecular structure from the all-particle wave function (PDF, 754 KB)
J. Chem. Phys. 135 2011 204302
Molecular structure is an input to quantum chemical calculations within the Born-Oppenheimer approximation. Hence, it is not obvious how molecular structure actually emerges in quantum mechanics. We have closed this gap here and present density distributions from which the molecular structure can be deduced.
32) E. Mátyus, J. Hutter, U. Müller-Herold, M. Reiher
On the emergence of molecular structure (PDF, 194 KB)
Phys. Rev. A 83 2011, 052512
He and H_2^+ both consist of three particles of which two are identical. Hence, the corresponding many-particle Schroedinger equation is of the same form for both cases and they only differ with respect to the mass ratio of the two different particles. Still, He is an atom (i.e., spherically symmetric), while H_2^+ is considered the simplest molecule. This conundrum is resolved in the paper.
31) M. Stiebritz, M. Reiher
A Unifying Structural and Electronic Concept for Hmd and [FeFe] Hydrogenase Active Sites
Inorg. Chem. 49 2010, 5818–5823
Hmd and [FeFe] hydrogenase seem to have very different active centers. However, a closer look reveals that they have much more in common than one would expect at first sight.
30) S. Fux, C. R. Jacob, J. Neugebauer, L. Visscher, M. Reiher
Accurate frozen-density embedding potentials as a first step towards a subsystem description of covalent bonds (PDF, 784 KB)
J. Chem. Phys. 132 2010, 164101
From accurate reference electron densities we construct frozen-density embedding potentials.
29) K. H. Marti, B. Bauer, M. Reiher, M. Troyer, F. Verstraete
Complete-Graph Tensor Network States: A New Fermionic Wave Function Ansatz for Molecules (PDF, 618 KB)
New J. Phys. 12 2010, 103008
This paper is the first implementation of tensor network states for molecules described by the full quantum-chemical many-electron Hamiltonian (previous work in different groups had considered much simpler spin model Hamiltonians only). Our tensor network envokes parameters between each pair of orbitals and considers the optimization of this complete pair correlation network. For this reason, we called the resulting approximation to the electronic wave function a complete-graph tensor network.
28) S. Luber, J. Neugebauer, M. Reiher
Enhancement and de-enhancement effects in vibrational resonance Raman optical activity (PDF, 1.5 MB)
J. Chem. Phys. 132 2010, 044113
We implemented resonance ROA theory and study the enhancement mechanism. It is one of the first such studies.
27) M. Reiher, A. Wolf
Relativistic Quantum Chemistry: The Fundamental Theory of Molecular Science
In this monograph, the semi-classical theory of relativistic quantum mechanics as needed for chemistry is developed from scratch. The 2nd edition was published in 2015
26) S. Schenk, B. Kirchner, M. Reiher
A Stable Six-Coordinate Intermediate in Ammonia-Dinitrogen Exchange at Schrock's Molybdenum Catalyst
Chem. Eur. J. 15 2009, 5073-5082
We were able to identify a six-coordinate intermediate of the important NH3 vs. N2 exchange at the very congested five-coordinate Schrock Mo catalyst for nitrogen fixation under ambient conditions.
25) K. H. Marti, M. Reiher
Haptic Quantum Chemistry
J. Comput. Chem. 30 2009, 2010-2020
Here, we introduced the new concept of Haptic Quantum Chemistry which addresses the human tactile sense and allows one to gain an enhanced chemical intuition about a reactive system and to explore its reactivity interactively. Combined with efficient input facilities, the approach will change the way quantum chemical calculation are carried out and interpreted as soon as an efficient software package becomes available, a task that we solved in 2014/2015.
24) C.R. Jacob, M. Reiher
Localizing Normal Modes in Large Molecules (PDF, 759 KB)
J. Chem. Phys. 130 2009, 084106
Although orbital localization is an old concept in molecular orbital theory, it had not been transfered to molecular vibrations. Normal modes, i.e., the eigenvectors of the Hessian matrix of second derivatives of the electronic energy with respect to nuclear coordinates, are also highly delocalized and we showed how unitary transformations can be constructed that localize these vibrations such that spectra of large molecules are easier to interpret. The localization criterion is not unique, but fortunately its choice does hardly affect the result. Normal modes and intensities can e reconstructed from the localized modes. These localized modes themselves resemble vibrations of isolated subunits but are not identical to them. Localized vibrations are important for the analysis of vibrational spectra. They are provided within the MoViPac program package (J. Comput. Chem. (2012) DOI: 10.1002/jcc.23036) and have also been implemented by Liegeois into the PyVib2 program.
23) S. Luber, M. Reiher
Intensity-carrying modes in Raman and Raman optical activity spectroscopy
ChemPhysChem 10 2009, 2049-2057
Intensity-carrying modes were rigorously defined for Raman spectroscopy and then subjected to our Intensity-Tracking algorithm.
22) K. Marti, I. Malkin Ondik, G. Moritz, M. Reiher
Density Matrix Renormalization Group Calculations on Relative Energies of Transition Metal Complexes and Clusters (PDF, 278 KB)
J. Chem. Phys. 128 2008, 014104
This is the first paper to advocate for the use of the DMRG algorithm in transition metal chemistry. Before this paper came out, DMRG was strictly believed to be only beneficial for systems with a (pseudo-)one-dimensional molecular structure because of the matrix-product-state structure of the DMRG wave function. By contrast, we could show that it is also efficient for compact, strongly correlated electronic structures such as those found in CoH and NiCO. Even for the pathological case of dicationic Cu2O2 we could demonstrate that the CASSCF failure is due to the limited active space, while DMRG was able to overcome this problem (see Phys. Rev. A 83 (2011) 012508 for a comparison of all DMRG results that were obtained for this cluster).
21) G. Eickerling, M. Reiher
The Shell Structure of Atoms
J. Chem. Theory Comput. 4 2008, 286-296
In Bader's book on Atoms in Molecules from 1990, he notes that the detection of shells in the atomic density becomes very difficult if not impossible for heavy atoms (say, beyond Ar). In this work, we presented a detailed relativistic study based on fully-relativistic numerical MCSCF results (obtained with our ADRIEN computer program) and could show that the atomic shell structure can be identified from features of the Laplacian of the density.
20) S. Schenk, B. Le Guennic, B. Kirchner, M. Reiher
First-Principles Investigation of the Schrock Mechanism of Dinitrogen Reduction Employing the Full HIPTN3N Ligand
Inorg. Chem. 47 2008, 3634-3650
While we already presented the first quantum chemical study of the full Schrock dinitrogen complex in 2005 (Inorg. Chem. 44 (2005), 9640; Chem. Eur. J. 11 (2005), 7448), this work completes our previous papers as now the thermodynamics of the whole catalytic cycle has been studied. The relevance of the work has been highlighted in a detailed comparison of experiment and theory by Schrock in Angew. Chem. Int. Ed. 47 (2008), 5512. Recently, we were able to map almost all side reactions related to protonation and reduction of this type of catalysis (J. Chem. Theory Comput. (2015) DOI: 10.1021/acs.jctc.5b00866).
19) K. Kiewisch, J. Neugebauer, M. Reiher
Selective Calculation of High-Intensity Vibrations in Molecular Resonance Raman Spectra (PDF, 497 KB)
J. Chem. Phys. 129 2008, 204103
This paper introduces the Intensity-Tracking algorithm as an inverse quantum-chemical approach to directly target only intense modes in a spectrum (and thus avoid the consideration of modes which do not pick up intensity). The algorithm is applied to resonance Raman spectroscopy for which it is most beneficial as this type of spectroscopy already focuses on a very small subset of the whole set of molecular vibrations by virtue of resonance selection.
18) S. Luber, M. Reiher
Raman Optical Activity Spectra of Chiral Transition Metal Complexes
Chem. Phys. 346 2008, 212-223
In this work, we describe our density-fitting implementation of Raman Optical Activity (ROA) property tensors which allows us to study very large molecules (a prominent example is the metallothionein published in J. Phys. Chem. B 114 (2010), 1057). As a side effect, we presented the first ROA spectra calculated for chiral transition metal complexes.
17) R. Mastalerz, R. Lindh, M. Reiher
The Douglas-Kroll-Hess Electron Density at an Atomic Nucleus
Chem. Phys. Lett. 465 2008, 157-164
The DKH density is not obtained from squared DKH orbitals. This holds for all unitary transformation schemes that decouple the Dirac Hamiltonian. Instead, a density operator must be employed that then requires unitary transformation before the density can be calculated. We have implemented this transformation and applied it to the calculation of relativistic contact densities relevant to various spectroscopic techniques.
16) G. Moritz, M. Reiher
Decomposition of Density Matrix Renormalization Group States into a Slater Determinant Basis (PDF, 2 MB)
J. Chem. Phys. 126 2007, 244109
In this work, we explicitly re-construct the full configuration interaction (FCI) expansion of the electronic wave function from a DMRG calculation. The technique was limited to cases for which we could also run a FCI calculation. However, we have solved this issue by introducing the sampling-reconstructing complete-active-space algorithm in later work (J. Chem. Phys. 134 (2011), 224101). Our 2008 paper also presents a detailed flow chart of the (first-generation) quantum-chemical DMRG algorithm.
15) C. Herrmann, M. Reiher, B. A. Hess
Comparative Analysis of Local Spin Definitions (PDF, 122 KB)
J. Chem. Phys. 122 2005, 034102
In this paper we implemented and investigated the local spin decomposition of Clark and Davidson. We corrected some of their equations and identified an inconsistency of the decomposition in closed-shell cases that sparked work in other groups, most notably by Mayer, Salvador and co-workers.
14) M. Reiher, B. Kirchner, J. Hutter, D. Sellmann, B. A. Hess
A Photochemical Activation Scheme of Inert Dinitrogen by Dinuclear RuII and FeII Transition Metal Complexes
Chem. Eur. J. 10 2004, 4443-4453
We demonstrate how a synthetic transition-metal complex can be brought to activate coordinated dinitrogen by photochemical excitation (a subsequent study elaborates on the dynamics of this process: Chem. Eur. J. 11 (2005), 574). Considering the fact that sustainable processes are now being thought for any important chemical transformation, this concept is significant in the field of dinitrogen photofixation.
13) M. Reiher, A. Wolf
Exact decoupling of the Dirac Hamiltonian. I. General Theory (PDF, 483 KB)
J. Chem. Phys. 121 2004, 2037-2047
This fundamental work discusses the two possible approaches for decoupling the Dirac Hamiltonian, i.e., the Foldy-Woutuysen and the Douglas-Kroll-Hess (DKH) unitary decoupling methods. It is explained why the Foldy-Woutuysen ansatz, i.e., the 1/c expansion is ill-defined and may only be used in perturbative approaches. Variational methods require the V-expansion of the DKH ansatz.
12) M. Reiher, A. Wolf
Exact decoupling of the Dirac Hamiltonian. II. The generalized Douglas-Kroll-Hess transformation up to arbitrary order (PDF, 486 KB)
J. Chem. Phys. 121 2004, 10945-10956
This work presents the first study of the convergence of DKH energies. It describes an automated protocol for the derivation of high-order DKH Hamiltonians that can be driven to any arbitrary order for the decoupling of positive- and negative-energy states of the Dirac Hamiltonian.
11) M. Reiher, J. Neugebauer
A mode-selective quantum chemical method for tracking molecular vibrations applied to functionalized carbon nanotubes (PDF, 586 KB)
J. Chem. Phys. 118 2003, 1634-1641
This paper introduces the Mode-Tracking approach as an inverse quantum-chemical method to directly target pre-selected vibrations without the need of calculating the full Hessian matrix (apart from the harmonic approximation, no additional approximation is introduced). A Davidson-based subspace iteration protocol is employed for this purpose. While its value is evident for large molecules (as the Hessian matrix need not be calculated), it is even very useful for small molecules that are treated with highly correlated quantum-chemical methods (e.g., coupled cluster). In the latter cases, the Hessian matrix is then of small dimension but its entries are extremely time-consuming to calculate. In this respect, subspace diagonalization techniques were shown to be important for the diagonalization of small matrices whose entries are difficult to obtain.
10) A. Wolf, M. Reiher, B. A. Hess
The generalized Douglas-Kroll transformation (PDF, 144 KB)
J. Chem. Phys. 117 2002, 9215-9226
Various parametrizations of the unitary transformation for the decoupling of the Dirac Hamiltonian are possible. Here, we proposed the most general one (embracing all existing approaches) that then allowed us to understand whether the resulting Hamiltonians depend on this choice. And they do: starting with 5th order, the transformed Hamiltonians depend on the chosen parametrization.
9) J. Neugebauer, M. Reiher, J. Hinze
Analysis of the asymptotic and short-range behaviour of quasilocal Hartree-Fock and Dirac-Fock electron-electron interaction potentials (PDF, 125 KB)
Phys. Rev A, 65 2002, 032518
Although being a very old theory in atomic physics, Hartree-Fock theory had not been fully analyzed with respect to the short-range behavior of the mean-field potentials. We close this gap for the nonrelativistic and also for the relativistic regime.
Analytical formulae are derived for the short-range limit, and we review the known facts on the long-range behavior.
8) B. Kirchner, M. Reiher
The secret of dimethyl sulfoxide (DMSO) water mixtures. A quantum chemical study of 1DMSO-nWater clusters
J. Am. Chem. Soc., 124 2002, 6206-6215
DMSO-water mixtures exhibit a prominent nonadditive behavior, which is difficult to explain. We carried out this cluster study in order to identify stable cluster structures that might be important in mixtures at interesting mole fractions. And indeed, a DMSO molecule exerts various ordering 'forces' that allow for hydrogen bonds from its methyl groups to surrounding water molecules and for peculiar structures such as the "ruessel structures" found.
7) J. Neugebauer, M. Reiher, C. Kind, B. A. Hess
Quantum Chemical Calculation of Vibrational Spectra of Large Molecules. Raman and IR spectra for Buckminsterfullerene
J. Comput. Chem. 23 2002, 895-910
While this paper got known as the SNF software paper, it contains unprecedented results such as the calculated Raman spectrum of buckminsterfullerene C60 in full icosahedral symmetry in a decent basis set. Before this paper came out, one could find rather strange conversion factors on how to obtain Raman intensities from ab initio caluclations performed in Hartree atomic units that can be compared to what is actually measured in experiment. Hence, we accompanied all our derivations, although textbook knowledge, by explicit units in order to clear up this mess.
6) G. Brehm, M. Reiher, S. Schneider
Estimation of the Vibrational Contribution to the Entropy Change Associated with the Low- to High-Spin Transition in Fe(phen)2(NCS)2 Complexes: Results Obtained by IR and Raman Spectroscopy and DFT Calculations
J. Phys. Chem. A 106 2002, 12024-12034
Here, we made an attempt toward a complete assignment of the vibrational spectrum of the prototypical thermal spincrossover complex Fe(phen)2(NCS)2 in order to calculate the entropy change of the entropy-driven thermal spincrossover phenomenon.
5) J. Neugebauer, M. Reiher, B. A. Hess
Coupled Cluster Raman Intensities: Assessment and Comparison with Multi-Configuration and Density Functional Methods (PDF, 165 KB)
J. Chem. Phys., 117 2002, 8623-8633
This paper presents the first assessment of calculated Raman intensities for non-linear molecules where DFT was compared to coupled-cluster and multi-configuration results.
4) M. Reiher, D. Sellmann, B. A. Hess
Stabilization of diazene in Fe(II)-sulfur model complexes for nitrogenase activity. Part I. A new approach to the evaluation of intramolecular hydrogen bond energies
Theor. Chem. Acc. 106 2001, 379-392
In this work, we proposed a new approach to estimate hydrogen bond energies suited for cases in which no rigorous decomposition analysis is possible, called the SEN approach.
We have exploited this idea in various studies of hydrogen-bonded systems. It was re-parametrized by Kirchner and co-workers (J. Phys. Chem. A, 110 (2006), 4229) and, for instance, applied by Gonzalez and co-workers (Int. J. Quantum Chem. 112 (2012), 1786).
3) M. Reiher, O. Salomon, B. A. Hess
Reparametrization of hybrid functionals based on energy differences of states of different multiplicity
Theor. Chem. Acc. 107 2001, 48-55
B3LYP* was invented in this paper. We realized that spin state energetics depend in a regular way on the exact exchange admixture and recommended to decrease the amount of exact exchange. In order to change the notorious B3LYP functional to the least necessary extent, we suggested the 15% admixture. It is know widely realized that the amount of exact exchange in contemporary functionals should not be too high for transition metal complexes (see, for example, the M06 family of Truhlar functionals and, in particular, the M06-L variant).
2) M. Reiher, J. Hinze
Self-consistent treatment of the frequency-independent Breit interaction in Dirac-Fock and MCSCF calculations of atomic structures: I. Theoretical considerations
J. Phys. B 32 1999, 5489-5505
The calculation of two-electron Breit interaction integrals is quite cumbersome. In this paper we rewrote the 1976 expression by Grant and Pyper in a very compact way and showed that potentials derived from this interaction can be conveniently obtained as solutions of radial Poisson-type equations.
1) A. Sundermann, M. Reiher, W. W. Schoeller
Isoelectronic Arduengo-Type Carbene Analogues with the Group IIIa Elements Boron, Aluminium, Gallium, and Indium
Eur. J. Inorg. Chem. 1 1998, 305-310
Arduengo carbenes, discovered in 1991, were the first stable carbenes found and enjoy wide-spread application as ligands in organometallic chemistry. The group-III isoelectronic anions were long unknown. We have predicted their stability in 1998, before they were actually found (i) with B by Nozaki et al. (Science, 314 (2006),113) and (ii) with Ga by Schmidbaur and co-workers (JACS 121 (1999), 9758). See also Chem. Rev. 111 (2011) 354 for a review, Jones and co-workers (Chem. Commun. (2002), 1196) for a dimeric In compound, and Hill and Hitchcock for a 6-membered In carbene analog (Chem. Commun. (2004), 1818).