From eb57011caaeeb01bbcdd9985cd2e75fa41f6e5b8 Mon Sep 17 00:00:00 2001
From: Hunter Belanger <hunter.belanger@gmail.com>
Date: Sat, 6 Jun 2026 13:44:50 +0200
Subject: [PATCH] Corrects off-by-one index error when storing fission energy
 release components

---
 src/endf/mf1.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/endf/mf1.py b/src/endf/mf1.py
index 24dee65..6cae536 100644
--- a/src/endf/mf1.py
+++ b/src/endf/mf1.py
@@ -191,7 +191,7 @@ def parse_mf1_mt458(file_obj: TextIO) -> dict:
             (_, _, LDRV, IFC), EIFC = get_tab1_record(file_obj)
 
             # Determine which component it is and replace in dictionary
-            name = components[IFC]
+            name = components[IFC-1]
             data[name] = {'LDRV': LDRV, 'EIFC': EIFC}
 
     return data