"valence isomer" meaning in English

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      "form": "valence isomers",
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  "lang_code": "en",
  "pos": "noun",
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      "derived": [
        {
          "word": "Dewar valence isomer"
        }
      ],
      "glosses": [
        "Any of a set of structural isomers that are related by a pericyclic reaction"
      ],
      "id": "en-valence_isomer-en-noun-XQ7-C146",
      "links": [
        [
          "chemistry",
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        [
          "structural isomer",
          "structural isomer"
        ],
        [
          "pericyclic reaction",
          "pericyclic reaction"
        ]
      ],
      "raw_glosses": [
        "(chemistry) Any of a set of structural isomers that are related by a pericyclic reaction"
      ],
      "topics": [
        "chemistry",
        "natural-sciences",
        "physical-sciences"
      ]
    }
  ],
  "word": "valence isomer"
}

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  "derived": [
    {
      "word": "Dewar valence isomer"
    }
  ],
  "forms": [
    {
      "form": "valence isomers",
      "tags": [
        "plural"
      ]
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      "glosses": [
        "Any of a set of structural isomers that are related by a pericyclic reaction"
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        [
          "chemistry",
          "chemistry"
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          "structural isomer",
          "structural isomer"
        ],
        [
          "pericyclic reaction",
          "pericyclic reaction"
        ]
      ],
      "raw_glosses": [
        "(chemistry) Any of a set of structural isomers that are related by a pericyclic reaction"
      ],
      "topics": [
        "chemistry",
        "natural-sciences",
        "physical-sciences"
      ]
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  ],
  "word": "valence isomer"
}