diff --git a/o/OVITO/OVITO-3.9.2-gompi-2022b-basic.eb b/o/OVITO/OVITO-3.9.2-gompi-2022b-basic.eb
index b6580c0f..06afff0e 100644
--- a/o/OVITO/OVITO-3.9.2-gompi-2022b-basic.eb
+++ b/o/OVITO/OVITO-3.9.2-gompi-2022b-basic.eb
@@ -22,7 +22,7 @@ builddependencies = [
 ]
 
 dependencies = [
-    ('Qt6', '6.5.3'),
+    ('Qt6', '6.6.0'),
 #    ('Qt5', '5.15.7'),
     ('HDF5', '1.14.0'),
     ('netCDF', '4.9.0'),
diff --git a/o/OpenMPI/OpenMPI-4.1.4-GCC-11.3.0.eb b/o/OpenMPI/OpenMPI-4.1.4-GCC-11.3.0.eb
index 695f9b18..607c46a5 100644
--- a/o/OpenMPI/OpenMPI-4.1.4-GCC-11.3.0.eb
+++ b/o/OpenMPI/OpenMPI-4.1.4-GCC-11.3.0.eb
@@ -41,6 +41,7 @@ configopts += '--with-hwloc=$EBROOTHWLOC '  # hwloc support
 configopts += '--with-slurm ' # Enable slurm
 configopts += '--enable-mpi-cxx '  # Enable building the C++ MPI bindings
 configopts += '--with-ucx=$EBROOTUCX '
+configopts += '--with-pmix=$EBROOTPMIX '
 
 osdependencies = [('libibverbs-dev', 'libibverbs-devel', 'rdma-core-devel')]
 
diff --git a/o/OpenMPI/OpenMPI-4.1.5-GCC-12.3.0.eb b/o/OpenMPI/OpenMPI-4.1.5-GCC-12.3.0.eb
new file mode 100644
index 00000000..4c9aa169
--- /dev/null
+++ b/o/OpenMPI/OpenMPI-4.1.5-GCC-12.3.0.eb
@@ -0,0 +1,86 @@
+# IT4Innovations
+# LK 2023
+
+name = 'OpenMPI'
+version = '4.1.5'
+
+homepage = 'https://www.open-mpi.org/'
+description = """The Open MPI Project is an open source MPI-3 implementation."""
+
+toolchain = {'name': 'GCC', 'version': '12.3.0'}
+
+source_urls = ['https://www.open-mpi.org/software/ompi/v%(version_major_minor)s/downloads']
+sources = [SOURCELOWER_TAR_BZ2]
+patches = [
+    'OpenMPI-4.1.1_build-with-internal-cuda-header.patch',
+    'OpenMPI-4.1.1_opal-datatype-cuda-performance.patch',
+    'OpenMPI-4.1.5_fix-pmix3x.patch',
+]
+checksums = [
+    {'openmpi-4.1.5.tar.bz2': 'a640986bc257389dd379886fdae6264c8cfa56bc98b71ce3ae3dfbd8ce61dbe3'},
+    {'OpenMPI-4.1.1_build-with-internal-cuda-header.patch':
+     '63eac52736bdf7644c480362440a7f1f0ae7c7cae47b7565f5635c41793f8c83'},
+    {'OpenMPI-4.1.1_opal-datatype-cuda-performance.patch':
+     'b767c7166cf0b32906132d58de5439c735193c9fd09ec3c5c11db8d5fa68750e'},
+    {'OpenMPI-4.1.5_fix-pmix3x.patch':
+     '46edac3dbf32f2a611d45e8a3c8edd3ae2f430eec16a1373b510315272115c40'},
+]
+
+builddependencies = [
+    ('pkgconf', '1.9.5'),
+    ('Perl', '5.36.1'),
+    ('Autotools', '20220317'),
+]
+
+dependencies = [
+    ('zlib', '1.2.13'),
+    ('hwloc', '2.9.1'),
+    ('libevent', '2.1.12'),
+    ('UCX', '1.14.1'),
+    ('libfabric', '1.18.0'),
+    ('PMIx', '4.2.4'),
+    ('UCC', '1.2.0'),
+]
+
+# Update configure to include changes from the "internal-cuda" patch
+# by running a subset of autogen.pl sufficient to achieve this
+# without doing the full, long-running regeneration.
+preconfigopts = ' && '.join([
+    'cd config',
+    'autom4te --language=m4sh opal_get_version.m4sh -o opal_get_version.sh',
+    'cd ..',
+    'autoconf',
+    'autoheader',
+    'aclocal',
+    'automake',
+    ''
+])
+
+# CUDA related patches and custom configure option can be removed if CUDA support isn't wanted.
+configopts = '--with-cuda=internal '
+configopts += '--enable-shared --enable-mpi-thread-multiple --with-verbs '
+configopts += '--enable-mpirun-prefix-by-default '
+configopts += '--with-hwloc=$EBROOTHWLOC '  # hwloc support
+configopts += '--with-slurm ' # Enable slurm
+configopts += '--enable-mpi-cxx '  # Enable building the C++ MPI bindings
+configopts += '--with-ucx=$EBROOTUCX '
+
+import os
+if os.environ.get("CLUSTERNAME") in ["BARBORA"]:
+   modextravars = {'OMPI_MCA_btl_openib_if_include': 'mlx5_0',
+                'OMPI_MCA_btl_tcp_if_include': '10.33.4.0/24',
+                'OMPI_MCA_orte_base_help_aggregate': '0',
+                'SLURM_MPI_TYPE': 'pmix_v4',
+   }
+elif os.environ.get("CLUSTERNAME") in ["KAROLINA"]:
+   modextravars = {'OMPI_MCA_btl_openib_if_include': 'mlx5_0',
+                'OMPI_MCA_orte_base_help_aggregate': '0',
+                'SLURM_MPI_TYPE': 'pmix_v4',
+   }
+else:
+   modextravars = {'OMPI_MCA_btl_openib_if_include': 'mlx4_0',
+                'OMPI_MCA_oob_tcp_if_include': '10.0.0.0/8',
+                'SLURM_MPI_TYPE': 'pmix_v4',
+   }
+
+moduleclass = 'mpi'
diff --git a/q/Qt6/Qt6-6.6.0-GCCcore-12.2.0.eb b/q/Qt6/Qt6-6.6.0-GCCcore-12.2.0.eb
new file mode 100644
index 00000000..999838ac
--- /dev/null
+++ b/q/Qt6/Qt6-6.6.0-GCCcore-12.2.0.eb
@@ -0,0 +1,99 @@
+# IT4Innovations
+# LK 2023
+
+easyblock = 'CMakeNinja'
+
+name = 'Qt6'
+version = '6.6.0'
+
+homepage = 'https://qt.io/'
+description = "Qt is a comprehensive cross-platform C++ application framework."
+
+toolchain = {'name': 'GCCcore', 'version': '12.2.0'}
+# AMD/intel cpu
+import os
+if os.environ.get("CLUSTERNAME") in ["KAROLINA"]:
+	toolchainopts = {'lowopt': True, 'optarch': 'march=core-avx2'}
+else:
+	toolchainopts = {'lowopt': True, 'optarch': False}
+
+# disabling use of -ftree-vectorize is required to avoid compilation failures on some systems (e.g. Intel Skylake X)
+#toolchainopts = {'vectorize': False}
+
+source_urls = [
+    'https://download.qt.io/official_releases/qt/%(version_major_minor)s/%(version)s/single/',
+    'https://download.qt.io/archive/qt/%(version_major_minor)s/%(version)s/single/',
+    'https://download.qt.io/new_archive/qt/%(version_major_minor)s/%(version)s/single/',
+]
+sources = ['qt-everywhere-src-%(version)s.tar.xz']
+#patches = [
+#    'Qt6-6.5.2_fix_OF-Gentoo.patch',
+#]
+checksums = [
+    {'qt-everywhere-src-6.6.0.tar.xz': '652538fcb5d175d8f8176c84c847b79177c87847b7273dccaec1897d80b50002'},
+#    {'Qt6-6.5.2_fix_OF-Gentoo.patch': '62c4b1abdeac69f40fd48f5e46f470f9f9c328fdb02ab8aceb9aa1885ad8c601'},
+]
+
+builddependencies = [
+    ('binutils', '2.39'),
+    ('pkgconf', '1.9.3'),
+    ('CMake', '3.24.3'),
+    ('Ninja', '1.11.1'),
+    # deps for QtWebEngine
+    ('Bison', '3.8.2'),
+    ('flex', '2.6.4'),
+    ('gperf', '3.1'),
+    ('re2c', '3.0'),
+]
+
+dependencies = [
+    ('double-conversion', '3.2.1'),
+    ('GLib', '2.75.0'),
+    ('PCRE2', '10.40'),
+    ('libpng', '1.6.38'),
+    ('LibTIFF', '4.4.0'),
+    ('libwebp', '1.3.1'),
+    ('JasPer', '4.0.0'),
+    ('HarfBuzz', '5.3.1'),
+    ('SQLite', '3.39.4'),
+    ('graphite2', '1.3.14'),
+#    ('assimp', '5.2.5'),  # for Qt 3D
+    ('FFmpeg', '5.1.2'),
+    ('X11', '20221110'),
+    ('fontconfig', '2.14.1'),
+    ('zlib', '1.2.12'),
+    ('Python', '3.10.8'),
+#   ('Python-bundle-PyPI', '2023.06'),  # WebEngine
+#    ('freetype', '2.12.1'),  # WebEngine
+    ('DBus', '1.15.2'),
+ #   ('libevent', '2.1.12'),  # WebEngine
+    ('libGLU', '9.0.2'),
+ #   ('libjpeg-turbo', '2.1.4'),  # WebEngine
+ #   ('NSS', '3.85'),  # WebEngine, required
+ #   ('snappy', '1.1.9'),  # WebEngine
+    ('OpenSSL', '1.1', '', SYSTEM),
+#    ('ICU', '72.1'),  # WebEngine, optional
+#    ('nodejs', '18.12.1'),  # WebEngine, required
+    # ('gRPC', '1.52.2'),  # WebEngine needs older Abseil/gRPC/protobuf
+]
+
+preconfigopts = 'sed -i "s/MultiMedia/Multimedia/g" ../qt-everywhere-src-%(version)s/qtcharts/CMakeLists.txt &&'  # Typo
+preconfigopts += 'sed -i "23i set(Python3_ROOT_DIR \\$ENV{EBROOTPYTHON})" ' \
+                 '../qt-everywhere-src-6.6.0/qtwebengine/src/gn/CMakeLists.txt &&'
+
+configopts = '-Wno-dev '
+configopts += '-DFEATURE_qtpdf_build=OFF '  # Requires CUPS
+configopts += '-DQT_AVOID_CMAKE_ARCHIVING_API=ON '
+configopts += '-DPython3_ROOT_DIR=$EBROOTPYTHON '
+#configopts += '-DBUILD_qtwayland=OFF '  # Does not work on CentOS 7
+# Removed from Qt6.0.0 but may be added back in the future
+# configopts += '-DBUILD_qtgamepad=OFF '  # Does not work on CentOS 7
+
+sanity_check_paths = {
+    'files': ['bin/qmake6', 'lib/libQt6Core.%s' % SHLIB_EXT ],
+    'dirs': ['include/QtCore' ],
+}
+
+sanity_check_commands = ['qmake6 --help']
+
+moduleclass = 'devel'