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Schema Field Reference

Complete reference for all metadata fields in pulse sequence annotations. Current schema: v0.0.3 (schemas/current).

Required Fields

Field Type Description Example
schema_version string Schema version "0.0.3"
sequence_version string Sequence version (semantic, X.Y.Z) "1.2.0"
title string Descriptive sequence name "SOFAST-HMQC"
authors array List of contributors ["Name <email>"]
created string Creation date (YYYY-MM-DD) "2024-01-15"
last_modified string Last modification date "2026-04-30"
repository string Repository identifier "github.com/user/repo"
status string Development status "stable"
experiment_type array Experiment keywords (controlled enum) [hmqc, 2d]

Optional Fields

Field Type Description Example
description string Detailed description (multi-line YAML literal allowed) "1H,15N SOFAST-HMQC..."
features array Technical features (open vocabulary — see VOCABULARY.md) [sofast, states_tppi]
typical_nuclei array Typical nuclei, ordered by channel f1, f2, ... [1H, 13C, 15N]
citation array Literature references ["Author et al., Journal (Year)"]
doi array DOI identifiers ["10.1021/ja051306e"]
dimensions array Indirect-dimension identifiers (dotted-path) [relaxation.duration, f1]
acquisition_order array Loop order, innermost to outermost [f1, relaxation.duration]
reference_pulse array Reference pulses for power calculations [{channel: f1, duration: p1, power: pl1}]

Controlled Vocabularies

Status Values

  • experimental: Under development, use with caution
  • beta: Testing phase, mostly stable
  • stable: Production ready, well tested
  • deprecated: No longer recommended

Nuclei Format

Use standard isotope notation: 1H, 13C, 15N, 31P, 19F, etc. Use nothing as a placeholder for unused channels.

Experiment Types (enum)

1d, 2d, 3d, cosy, tocsy, noesy, hsqc, hmqc, trosy, relaxation, r1rho, cest, diffusion, calibration, solid_state

Common Features

  • Relaxation: R1, R2, cpmg, hahn_echo, perfect_echo, inversion_recovery, relaxation_dispersion, temperature_compensation, broadband
  • Spinlock: on_resonance, off_resonance
  • Diffusion: ste, xste, led
  • Excitation: selective_excitation, sofast, alsofast
  • Calibration: nutation, condenz
  • Water suppression: watergate, presaturation, water_suppression
  • Detection: states_tppi, phase_sensitive, magnitude_mode

Parameter values

Several block fields (power, duration, offset, gradient_strength, ...) accept any of:

  • a Bruker parameter name string (p1, d20, cnst25, pl25, taulist, vplist, F19sat)
  • a numeric literal
  • a linear sweep: {type: linear, start: <param|number>, end|step: <param|number>, scale: <param|number>} — type defaults to linear. scale is a multiplicative factor applied to the swept values; the dimension size is set elsewhere (TD).
  • a counter × scale expression: {counter: <param>, scale: <param|number>} (e.g. CPMG {counter: ncyc, scale: d20}).

Experiment-specific blocks

Each block extends a common shape (channel, power, duration, offset, type, model) with additional fields where needed.

relaxation

Fields: type (R1, R2), model (exponential-decay, inversion_recovery, saturation_recovery), channel, duration.

;@ experiment_type: [relaxation, 1d]
;@ relaxation: {type: R1, model: inversion_recovery, channel: f1, duration: t1delay}

CPMG (counter × spacing):

;@ experiment_type: [relaxation, 1d]
;@ features: [R2, cpmg, broadband]
;@ relaxation: {type: R2, model: exponential-decay, channel: f1, duration: {counter: ncyc, scale: d20}}

r1rho, cest

Fields: channel, power, duration, offset. Power, duration and offset are typically VA/VP/FQ lists referenced by name.

;@ experiment_type: [r1rho, 1d]
;@ r1rho: {channel: f1, power: powerlist, duration: taulist, offset: 0}

;@ experiment_type: [cest, 1d]
;@ cest: {channel: f1, power: pl25, duration: d18, offset: F19sat}

calibration

Fields: type (e.g. nutation, condenz), channel, power, duration, offset, model.

;@ experiment_type: [calibration, 1d]
;@ calibration:
;@   type: nutation
;@   channel: f1
;@   power: pl8
;@   duration: {type: linear, start: p9, step: p9}
;@   model: sine_modulated

diffusion

Fields: type (bipolar), coherence ([channel, coherence_order]), big_delta, little_delta, tau, gradient_strength, gradient_shape.

;@ experiment_type: [diffusion, 1d]
;@ diffusion:
;@   type: bipolar
;@   coherence: [f1, 1]
;@   big_delta: d20
;@   little_delta: p31
;@   tau: d17
;@   gradient_strength: {type: linear, start: cnst1, end: cnst2, scale: gpz6}
;@   gradient_shape: gpnam6