Abstract
<jats:p>The VAMAS Surface Chemical Analysis Standard Data Transfer Format, published in 1988 and subsequently standardized as ISO 14976:1998, remains an important vendor-neutral interchange format for X-ray photoelectron spectroscopy and other surface-analysis techniques. Its scientific information model is broad and unusually precise, but its serialization is positional: the meaning and number of later records depend on experiment modes, scan modes, counts and parameter-inclusion rules encountered earlier in the file. This makes archival interpretation dependent on specialist software, much of which implements only a subset of the permitted grammar. We present VAMAS-XML, an open-source Python reference implementation for bidirectional conversion between VAMAS/ISO 14976 text and a labelled XML representation. The XML is an alternative serialization of the existing information model, not a new scientific format. Source lexical forms, whitespace, line endings, comments, parameter-selection choices, numerical values and structural alternatives are retained so that VAMAS to XML to VAMAS conversion can be byte-identical. The XML additionally records a SHA-256 digest, filesystem timestamps and structured diagnostics. XML Schema, Schematron and application-level checks separate XML validity from compliance of the source VAMAS record. The converter is designed for unattended migration of large archives amomg other applications. It tolerates mechanically recognisable deviations, including mixed line endings, case variants, padded identifiers, inaccurate comment counts, non-finite numeric tokens, leading or trailing records, and an over-declared block count when an explicit experiment terminator is present.</jats:p>