diff --git a/base_classes/NXdetector_reference_frame.nxdl.xml b/base_classes/NXdetector_reference_frame.nxdl.xml
deleted file mode 100644
index c04fff024..000000000
--- a/base_classes/NXdetector_reference_frame.nxdl.xml
+++ /dev/null
@@ -1,52 +0,0 @@
-<?xml version='1.0' encoding='UTF-8'?>
-<?xml-stylesheet type="text/xsl" href="nxdlformat.xsl"?>
-<!--
-# NeXus - Neutron and X-ray Common Data Format
-#
-# Copyright (C) 2014-2024 NeXus International Advisory Committee (NIAC)
-#
-# This library is free software; you can redistribute it and/or
-# modify it under the terms of the GNU Lesser General Public
-# License as published by the Free Software Foundation; either
-# version 3 of the License, or (at your option) any later version.
-#
-# This library is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-# Lesser General Public License for more details.
-#
-# You should have received a copy of the GNU Lesser General Public
-# License along with this library; if not, write to the Free Software
-# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
-#
-# For further information, see http://www.nexusformat.org
--->
-<definition xmlns="http://definition.nexusformat.org/nxdl/3.1" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" category="base" type="group" name="NXdetector_reference_frame" extends="NXcoordinate_system" xsi:schemaLocation="http://definition.nexusformat.org/nxdl/3.1 ../nxdl.xsd">
-    <doc>
-        Details about the detector_reference_frame for a specific detector.
-        
-        It is assumed that the configuration is inspected by looking towards
-        the sample surface from a position that is located behind the detector.
-        
-        If any of these assumptions is not met, the user is required to 
-        explicitly state this.
-        
-        `Reference &lt;https://doi.org/10.1016/j.matchar.2016.04.008&gt;`_ suggests to label
-        the  base vectors of this coordinate system as :math:`X_d, Y_d, Z_d`.
-    </doc>
-    <field name="x_alias" type="NX_CHAR">
-        <!--<enumeration>
-             <item value="Xd"/>
-        </enumeration>-->
-    </field>
-    <field name="y_alias" type="NX_CHAR">
-        <!--<enumeration>
-             <item value="Yd"/>
-        </enumeration>-->
-    </field>
-    <field name="z_alias" type="NX_CHAR">
-        <!--<enumeration>
-             <item value="Zd"/>
-        </enumeration>-->
-    </field>
-</definition>
\ No newline at end of file
diff --git a/base_classes/NXprocessing_reference_frame.nxdl.xml b/base_classes/NXprocessing_reference_frame.nxdl.xml
deleted file mode 100644
index 1b420d686..000000000
--- a/base_classes/NXprocessing_reference_frame.nxdl.xml
+++ /dev/null
@@ -1,66 +0,0 @@
-<?xml version='1.0' encoding='UTF-8'?>
-<?xml-stylesheet type="text/xsl" href="nxdlformat.xsl"?>
-<!--
-# NeXus - Neutron and X-ray Common Data Format
-#
-# Copyright (C) 2014-2024 NeXus International Advisory Committee (NIAC)
-#
-# This library is free software; you can redistribute it and/or
-# modify it under the terms of the GNU Lesser General Public
-# License as published by the Free Software Foundation; either
-# version 3 of the License, or (at your option) any later version.
-#
-# This library is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-# Lesser General Public License for more details.
-#
-# You should have received a copy of the GNU Lesser General Public
-# License along with this library; if not, write to the Free Software
-# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
-#
-# For further information, see http://www.nexusformat.org
--->
-<definition xmlns="http://definition.nexusformat.org/nxdl/3.1" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" category="base" type="group" name="NXprocessing_reference_frame" extends="NXcoordinate_system" xsi:schemaLocation="http://definition.nexusformat.org/nxdl/3.1 ../nxdl.xsd">
-    <doc>
-        Base class to document details about processing reference frames.
-        
-        Directional differences in processing materials can cause anisotropies
-        of material properties. Mechanical processing is one example where
-        the rotation of the NXsample_reference_frame with respect to another
-        processing_reference_frame is relevant.
-        
-        Fields with suffix alias should be used to specify 
-
-        how the base vectors of the reference frame for the (macroscopic) sampleare aligned different
-        directions (e.g. rolling, transverse, and normal direction) align how with the direction of the base vectors of the 
-        :ref:`NXsample_reference_frame`.
-        
-        It is assumed that the configuration is inspected by looking towards
-        the sample surface. If a detector is involved, it is assumed that the
-        configuration is inspected from a position that is located behind this
-        detector.
-        
-        If any of these assumptions is not met, the user is required to
-        explicitly state this.
-        
-        `Reference &lt;https://doi.org/10.1016/j.matchar.2016.04.008&gt;`_ suggests to label the base
-        the base vectors of this coordinate system as :math:`X_p, Y_p, Z_p`.
-    </doc>
-    <field name="x_alias" type="NX_CHAR">
-        <doc>Alias 
-        <!--<enumeration>
-             <item value="Xp"/>
-        </enumeration>-->
-    </field>
-    <field name="y_alias" type="NX_CHAR">
-        <!--<enumeration>
-             <item value="Yp"/>
-        </enumeration>-->
-    </field>
-    <field name="z_alias" type="NX_CHAR">
-        <!--<enumeration>
-             <item value="Zp"/>
-        </enumeration>-->
-    </field>
-</definition>
\ No newline at end of file
diff --git a/base_classes/NXsample_reference_frame.nxdl.xml b/base_classes/NXsample_reference_frame.nxdl.xml
deleted file mode 100644
index f6813b458..000000000
--- a/base_classes/NXsample_reference_frame.nxdl.xml
+++ /dev/null
@@ -1,55 +0,0 @@
-<?xml version='1.0' encoding='UTF-8'?>
-<?xml-stylesheet type="text/xsl" href="nxdlformat.xsl"?>
-<!--
-# NeXus - Neutron and X-ray Common Data Format
-#
-# Copyright (C) 2014-2024 NeXus International Advisory Committee (NIAC)
-#
-# This library is free software; you can redistribute it and/or
-# modify it under the terms of the GNU Lesser General Public
-# License as published by the Free Software Foundation; either
-# version 3 of the License, or (at your option) any later version.
-#
-# This library is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-# Lesser General Public License for more details.
-#
-# You should have received a copy of the GNU Lesser General Public
-# License along with this library; if not, write to the Free Software
-# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
-#
-# For further information, see http://www.nexusformat.org
--->
-<definition xmlns="http://definition.nexusformat.org/nxdl/3.1" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" category="base" type="group" name="NXsample_reference_frame" extends="NXcoordinate_system" xsi:schemaLocation="http://definition.nexusformat.org/nxdl/3.1 ../nxdl.xsd">
-    <doc>
-        Details about the sample reference frame that is typically overlaid
-        onto the surface of the sample.
-             
-        It is assumed that the configuration is inspected by looking towards
-        the sample surface. If a detector is involved, it is assumed that the 
-        configuration is inspected from a position that is located behind this
-        detector.
-        
-        If any of these assumptions is not met, the user is required to
-        explicitly state this.
-        
-        `Reference &lt;https://doi.org/10.1016/j.matchar.2016.04.008&gt;`_ suggests to label the base
-        vectors of this coordinate system as :math:`X_s, Y_s, Z_s`.
-    </doc>
-    <field name="x_alias" type="NX_CHAR">
-        <!--<enumeration>
-             <item value="Xs"/>
-        </enumeration>-->
-    </field>
-    <field name="y_alias" type="NX_CHAR">
-        <!--<enumeration>
-             <item value="Ys"/>
-        </enumeration>-->
-    </field>
-    <field name="z_alias" type="NX_CHAR">
-        <!--<enumeration>
-             <item value="Zs"/>
-        </enumeration>-->
-    </field>
-</definition>
\ No newline at end of file