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In carbon-13 NMR spectra, chloroform-d ($CDCl_3$) appears as a triplet at about 77 ppm.
This is because
hydrogen atoms are decoupled from carbon-13, and this causes deuterium to show as a triplet.
deuterium nuclear signals are split by attached carbon-13 nuclei.
carbon-13 nuclear signals are split by attached deuterium nuclei.
carbon-13 nuclei are split by all attached hydrogen atoms, whether protium or deuterium, but the splitting is much larger for deuterium and is therefore visible.
deuterium's NMR resonance frequencies overlap with the resonance frequencies of carbon-13 atoms.