NXms

Status:

application definition, extends NXobject

Description:

Application definition, spatiotemporal characterization of a microstructure.

Symbols:

The symbols used in the schema to specify e.g. dimensions of arrays.

n_b: Number of boundaries of the bounding box or primitive to domain.

n_p: Number of parameter required for chosen orientation parameterization.

c: Number of texture components identified.

Groups cited:

NXcg_grid, NXcg_hexahedron_set, NXcg_point_set, NXcg_polyhedron_set, NXcg_roi_set, NXcoordinate_system_set, NXdata, NXem_ebsd_conventions, NXentry, NXms_atom_set, NXms_dislocation_set, NXms_interface_set, NXms_snapshot_set, NXms_snapshot, NXorientation_set, NXprocess, NXprogram, NXsample, NXtransformations, NXuser

Structure:

ENTRY: (required) NXentry

@version: (required) NX_CHAR

An at least as strong as SHA256 hashvalue of the file that specifies the application definition.

definition: (required) NX_CHAR

NeXus NXDL schema to which this file conforms.

Obligatory value: NXms

workflow_identifier: (required) NX_CHAR

Ideally, a (globally) unique persistent identifier for referring to this experiment or computer simulation.

The identifier is usually defined/issued by the facility, laboratory, or the principle investigator. The identifier enables to link experiments to e.g. proposals.

workflow_description: (optional) NX_CHAR

Free-text description about the workflow (experiment/analysis/simulation).

Users are strongly advised to detail the sample history in the respective field and fill rather as completely as possible the fields of this application definition rather than write details about the experiment into this free-text description field.

start_time: (required) NX_DATE_TIME

ISO 8601 time code with local time zone offset to UTC information included when the characterization started.

end_time: (recommended) NX_DATE_TIME

ISO 8601 time code with local time zone offset to UTC included when the characterization ended.

experiment_or_simulation: (required) NX_CHAR

Specify if the (characterization) results/data of this instance of an application definition are based on the results of a simulation or the results of a post-processing of measured data to describe a microstructure. The term microstructure is used to describe the spatial arrangement of crystal defects inside a sample/specimen without demanding necessarily that this structure is mainly at the micron length scale. Nanostructure and macrostructure are close synonyms. Material architecture is a narrow synonym.

Any of these values: experiment | simulation

PROGRAM: (required) NXprogram

program_name: (required) NX_CHAR

@version: (required) NX_CHAR

USER: (optional) NXuser

Contact information and eventually details of at least one person involved in creating this result. This can be the principle investigator who performed this experiment. Adding multiple users if relevant is recommended.

name: (required) NX_CHAR

Given (first) name and surname of the user.

affiliation: (recommended) NX_CHAR

Name of the affiliation of the user at the point in time when the experiment was performed.

address: (recommended) NX_CHAR

Postal address of the affiliation.

email: (recommended) NX_CHAR

Email address of the user at the point in time when the experiment was performed. Writing the most permanently used email is recommended.

orcid: (recommended) NX_CHAR

Globally unique identifier of the user as offered by services like ORCID or ResearcherID. If this field is field the specific service should also be written in orcid_platform

orcid_platform: (recommended) NX_CHAR

Name of the OrcID or ResearcherID where the account under orcid is registered.

telephone_number: (optional) NX_CHAR

(Business) (tele)phone number of the user at the point in time when the experiment was performed.

role: (recommended) NX_CHAR

Which role does the user have in the place and at the point in time when the experiment was performed? Technician operating the microscope. Student, postdoc, principle investigator, guest are common examples.

social_media_name: (optional) NX_CHAR

Account name that is associated with the user in social media platforms.

social_media_platform: (optional) NX_CHAR

Name of the social media platform where the account under social_media_name is registered.

specimen: (required) NXsample

name: (required) NX_CHAR

Descriptive name or ideally (globally) unique persistent identifier.

DATA: (optional) NXdata

Hard link to a location in the hierarchy of the NeXus file where the data for default plotting are stored.

COORDINATE_SYSTEM_SET: (required) NXcoordinate_system_set

Container to hold different coordinate systems conventions. A least a right-handed Cartesian coordinate system with base vectors named x, y, and z has to be specified. Using one NXtransformations instance per base vector.

TRANSFORMATIONS: (minOccurs=3) NXtransformations

conventions: (required) NXem_ebsd_conventions

rotation_conventions: (required) NXprocess

three_dimensional_rotation_handedness: (required) NX_CHAR

rotation_convention: (required) NX_CHAR

euler_angle_convention: (required) NX_CHAR

axis_angle_convention: (required) NX_CHAR

orientation_parameterization_sign_convention: (required) NX_CHAR

processing_reference_frame: (required) NXprocess

reference_frame_type: (required) NX_CHAR

xaxis_direction: (required) NX_CHAR

xaxis_alias: (required) NX_CHAR

yaxis_direction: (required) NX_CHAR

yaxis_alias: (required) NX_CHAR

zaxis_direction: (required) NX_CHAR

zaxis_alias: (required) NX_CHAR

origin: (required) NX_CHAR

sample_reference_frame: (required) NXprocess

reference_frame_type: (required) NX_CHAR

xaxis_direction: (required) NX_CHAR

yaxis_direction: (required) NX_CHAR

zaxis_direction: (required) NX_CHAR

origin: (required) NX_CHAR

ROI_SET: (required) NXcg_roi_set

The simulated or characterized material volume element aka domain. At least one instance of geometry required either NXcg_grid, NXcg_polyhedron_set, or NXcg_point_set. This geometry group needs to contain details about the boundary conditions.

grid: (optional) NXcg_grid

polyhedron_set: (optional) NXcg_polyhedron_set

point_set: (optional) NXcg_point_set

boundary: (optional) NXcg_hexahedron_set

A boundary to the volume element. Either an instance of NXcg_hexahedron_set or of NXcg_ellipsoid_set.

number_of_boundaries: (required) NX_POSINT {units=NX_UNITLESS}

How many distinct boundaries are distinguished. Value required equal to n_b.

boundaries: (required) NX_CHAR (Rank: 1, Dimensions: [n_b])

Name of the boundaries. E.g. left, right, front, back, bottom, top,

boundary_conditions: (required) NX_UINT (Rank: 1, Dimensions: [n_b]) {units=NX_UNITLESS}

The boundary conditions for each boundary:

0 - undefined 1 - open 2 - periodic 3 - mirror 4 - von Neumann 5 - Dirichlet

snapshot_set: (required) NXms_snapshot_set

Collection of microstructural data observed/simulated.

identifier_offset: (required) NX_UINT {units=NX_UNITLESS}

Integer which specifies the first index to be used for distinguishing snapshots. Identifiers are defined either implicitly or explicitly. For implicit indexing the identifiers are defined on the interval [identifier_offset, identifier_offset+c-1]. For explicit indexing the identifier array has to be defined.

The identifier_offset field can for example be used to communicate if the identifiers are expected to start from 1 (referred to as Fortran-/Matlab-) or from 0 (referred to as C-, Python-style index notation) respectively.

evolution: (optional) NXprocess

Summary quantities which are the result of some post-processing of the snapshot data (averaging, integrating, interpolating). Frequently used descriptors from continuum mechanics and thermodynamics can be used here. A few examples are given. Each descriptor is currently modelled as an instance of an NXprocess because it is relevant to understand how the descriptors are computed.

temperature: (optional) NXprocess

pressure: (optional) NXprocess

stress: (optional) NXprocess

strain: (optional) NXprocess

deformation_gradient: (optional) NXprocess

magnetic_field: (optional) NXprocess

electric_field: (optional) NXprocess

recrystallization_kinetics: (optional) NXprocess

grain_size_distribution: (optional) NXprocess

recrystallization_front: (optional) NXprocess

MS_SNAPSHOT: (required) NXms_snapshot

time: (required) NX_NUMBER {units=NX_TIME}

Measured or simulated physical time stamp for this snapshot. Not to be confused with wall-clock timing or profiling data.

iteration: (required) NX_UINT {units=NX_UNITLESS}

Iteration or increment counter.

grid: (optional) NXcg_grid

polyhedron_set: (optional) NXcg_polyhedron_set

point_set: (optional) NXcg_point_set

MS_ATOM_SET: (optional) NXms_atom_set

Details about statistically or explicitly resolved atoms in the entire domain.

MS_DISLOCATION_SET: (optional) NXms_dislocation_set

Details about statistically or explicitly resolved dislocations in the entire domain.

MS_INTERFACE_SET: (optional) NXms_interface_set

Details about statistically or explicitly resolved interfaces between crystals in the entire domain.

odf: (optional) NXprocess

Details about the orientation distribution function within the entire domain.

computation_method: (required) NX_CHAR

With which method was the ODF approximated?

texture_index: (optional) NX_NUMBER {units=NX_ANY}

TO BE DEFINED

texture_strength: (optional) NX_NUMBER {units=NX_ANY}

TO BE DEFINED

volume_statistics: (optional) NXorientation_set

Collection of texture components commonly referred to.

parameterization: (required) NX_CHAR

Any of these values: bunge-euler (ZXZ) | quaternion

orientation: (required) NX_NUMBER (Rank: 2, Dimensions: [c, n_p]) {units=NX_ANY}

Parameterized orientations.

name: (required) NX_CHAR (Rank: 1, Dimensions: [c])

Name of each texture component, e.g. Cube, Dillamore, Y.

integration_radius: (required) NX_NUMBER (Rank: 1, Dimensions: [c]) {units=NX_ANGLE}

The portion of orientation space integrated over to compute the volume fraction.

volume_fraction: (required) NX_NUMBER (Rank: 1, Dimensions: [c]) {units=NX_DIMENSIONLESS}

The volume fraction of each texture component.

TRANSFORMATIONS: (required) NXtransformations

Reference to or definition of a coordinate system with which the definitions are interpretable.

modf: (optional) NXprocess

Details about the disorientation distribution function within the entire domain.

gbcd: (optional) NXprocess

Details about the grain boundary character distribution within the entire domain.

temperature: (optional) NXprocess

pressure: (optional) NXprocess

stress: (optional) NXprocess

strain: (optional) NXprocess

deformation_gradient: (optional) NXprocess

magnetic_field: (optional) NXprocess

electric_field: (optional) NXprocess

recrystallization_kinetics: (optional) NXprocess

grain_size_distribution: (optional) NXprocess

recrystallization_front: (optional) NXprocess

Hypertext Anchors

List of hypertext anchors for all groups, fields, attributes, and links defined in this class.

NXDL Source:

https://github.com/FAIRmat-Experimental/nexus_definitions/tree/fairmat/contributed_definitions/NXms.nxdl.xml