Ethanol — XYZ Cartesian Coordinates (.xyz)
The same ethanol geometry in XYZ format: an atom count, a free-text comment line and one line of element and coordinates per atom. XYZ carries no connectivity at all, so converting to it from the molfile is a lossy operation that this pair makes measurable.
9
ethanol, idealised geometry, coordinates in angstrom
C -1.245600 0.243600 0.000000
C 0.000000 -0.587600 0.000000
O 1.163600 0.229600 0.000000
H -2.134500 -0.386100 0.000000
H -1.273400 0.879700 0.883700
H -1.273400 0.879700 -0.883700
H 0.038400 -1.227000 0.885000
H 0.038400 -1.227000 -0.885000
H 1.952400 -0.317500 0.000000
Specifications
- Format
- XYZ
- Atoms
- 9
- Units
- angstrom
- Header Lines
- 2
- Connectivity
- none — XYZ stores no bonds
- Same Geometry As
- the ethanol molfile
Testing contract
Expected to pass- Scenario
- Parse the file and compare its coordinates against the paired molfile, then look for bond information.
- Expected result
- All nine coordinate triples match the molfile to four decimals, and no bond data exists anywhere in the file — a converter that claims to preserve connectivity is wrong.
What is a .xyz file?
The XYZ format is the simplest way to write a molecular geometry: a first line giving the atom count, a free-form comment line, and then one line per atom with an element symbol and Cartesian x, y, and z coordinates in ångströms. It records no bonds, charges, or connectivity. Multi-frame files simply concatenate blocks, which is how trajectories are stored.
How to use this file
Use an example .xyz file to test molecular viewers, format converters, and trajectory readers, checking that the declared atom count matches the block, that the comment line is not mistaken for data, and that concatenated frames are split correctly.
How to use this file for testing
“Ethanol — XYZ Cartesian Coordinates (.xyz)” is a deterministic Novus Examples fixture for Scientific data, Editor testing, Conversion testing. Citation catalogs (BibTeX, RIS), chemistry structures (MDL Molfile, PDB), and gridded binary data (NetCDF, FITS) — for testing reference managers, molecule viewers, and scientific-data loaders.
Documented properties for this file: XYZ. Compare results against paired or grouped companions on this page when present (clean↔damaged, searchable↔scanned, or format twins) so scores stay reproducible across runs.
Download the file once, keep the path stable in CI or local scripts, and treat the spec table as the contract: dimensions, seeds, field lists, and roles are intentional. Corrupt or invalid samples are labelled as such — expect parsers to fail loudly rather than silently accept them.
Scientific fixtures are small, valid, and fully synthetic — no real organism, patient, sample, or observation. Point your parser or loader at the file and check it reads the documented records, variables, or headers; binary formats ship a readable twin or metadata listing for comparison.
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