# Quantum crystallography and the use of kernel projector matrices

@article{Massa1995QuantumCA, title={Quantum crystallography and the use of kernel projector matrices}, author={L. Massa and L. Huang and J. Karle}, journal={International Journal of Quantum Chemistry}, year={1995}, volume={56}, pages={371-384} }

Quantum crystallography is a developing technique for extracting quantum mechanically valid properties from X-ray diffraction experiments. Quantum mechanics and crystallography are joined through the fact that the electron distributions around atoms are the source of X-ray diffraction and electron density distributions are observables that lend themselves readily to quantum mechanical description. Direct contact with the X-ray diffraction data is made by equating the structure factor magnitudes… Expand

#### 65 Citations

Quantum Crystallography: Features and Application

- Physics
- 1999

Quantum crystallography (QCr) is an area of research that arises from the fact that experimental X-ray diffraction data obtained from crystals can also be readily described theoretically by the use… Expand

Generalized formulation of quantum and classical crystallography using Green's functions

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Quantum crystallography is a methodology by which structural information about a crystalline material obtained from X-ray crystallography is combined with quantum mechanical methods. The objective is… Expand

Quantum crystallography: A perspective

- Physics, Computer Science
- J. Comput. Chem.
- 2018

Applications to crystals show that quantum mechanical density matrices of large molecules can be extracted from X‐ray scattering data by implementing a fragmentation method termed the kernel energy method (KEM), and how KEM can be used within the context of quantum crystallography to derive quantum mechanical properties of biological molecules. Expand

Quantum Crystallography: Current Developments and Future Perspectives.

- Chemistry, Medicine
- Chemistry
- 2018

An overview over current research that is related to a broader notion of QCr is given, and options how QCr can evolve to become a complete and independent domain of natural sciences are discussed. Expand

Exploiting the full quantum crystallography

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- 2018

Quantum crystallography (QCr) is a branch of crystallography aimed at obtaining the complete quantum mechanics of a crystal given its X-ray scattering data. The fundamental value of obtaining an… Expand

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- Medicine, Chemistry
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- 2020

By relying on approximations taken from orbital-free DFT, all components of the inner-crystal force can be easily retrieved from multipole-model refined experimental electron densities and their derivatives, and are becoming easily doable for any X-ray density crystallographer thanks to a new version of the computer program WinXPRO. Expand

Density functional theory in relation to x‐ray and neutron scattering experiments

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X-ray scattering allows, for example, the ground-state electron density of a crystal, say hexagonal close-packed Be, or a molecular solid, to be extracted. Two routes will be discussed by means of… Expand

Validation of X-ray Wavefunction Refinement.

- Medicine
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The obvious problems with the description of polar bonds in the MM are significantly reduced by using XWR and modeling of electron density in the vicinity of hydrogen atoms with XWR is visibly improved. Expand

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- 2017

The technique of quantitative convergent-beam electron diffraction (QCBED) is reviewed as a method for making very accurate and precise measurements of low-order bonding-sensitive structure factors.… Expand

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- 2020

By rephrasing the incipit of one of the most influential books: a spectre is haunting science, the spectre of quantum crystallography. This name is ever more frequent in the scientific literature and… Expand

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