diff --git a/CAT/__version__.py b/CAT/__version__.py
index e84a08af..25acc07a 100644
--- a/CAT/__version__.py
+++ b/CAT/__version__.py
@@ -1,3 +1,3 @@
 """The **CAT** version."""
 
-__version__ = '0.10.0'
+__version__ = '0.10.1'
diff --git a/CAT/attachment/ligand_anchoring.py b/CAT/attachment/ligand_anchoring.py
index 988469b2..405b3600 100644
--- a/CAT/attachment/ligand_anchoring.py
+++ b/CAT/attachment/ligand_anchoring.py
@@ -34,7 +34,7 @@
 from rdkit import Chem
 
 from ..logger import logger
-from ..utils import get_template, AnchorTup
+from ..utils import get_template, AnchorTup, KindEnum
 from ..mol_utils import separate_mod   # noqa: F401
 from ..workflows import MOL, FORMULA, HDF5_INDEX, OPT
 from ..settings_dataframe import SettingsDataFrame
@@ -286,7 +286,13 @@ def substructure_split(
 
     # Update ligand properties
     lig.properties.dummies = anchor
-    lig.properties.anchor = "".join(f"{lig[1 + i].symbol}{1 + i}" for i in anchor_tup.anchor_idx)
+    if anchor_tup.kind == KindEnum.FIRST:
+        i = 1 + anchor_tup.anchor_idx[0]
+        lig.properties.anchor = f"{lig[i].symbol}{i}"
+    else:
+        lig.properties.anchor = "".join(
+            f"{lig[1 + i].symbol}{1 + i}" for i in anchor_tup.anchor_idx
+        )
     lig.properties.anchor_tup = anchor_tup
     lig.properties.charge = sum(atom.properties.get('charge', 0) for atom in lig)
 
diff --git a/CAT/attachment/ligand_opt.py b/CAT/attachment/ligand_opt.py
index 589be1b8..496d06a1 100644
--- a/CAT/attachment/ligand_opt.py
+++ b/CAT/attachment/ligand_opt.py
@@ -42,7 +42,7 @@
 from rdkit.Chem import AllChem, Mol
 from scm.plams.core.basejob import Job
 from scm.plams import (Molecule, Atom, Bond, MoleculeError, add_to_class, Units,
-                       Settings, AMSJob, ADFJob, Cp2kJob)
+                       Settings, AMSJob, ADFJob, Cp2kJob, axis_rotation_matrix)
 
 from .mol_split_cm import SplitMol
 from .remove_atoms_cm import RemoveAtoms
@@ -190,11 +190,14 @@ def optimize_ligand(ligand: Molecule) -> None:
     allign_axis(ligand)
 
 
-def _get_allign_args(mol: "Molecule | Mol", anchor_tup: AnchorTup) -> Tuple[np.ndarray, int, int]:
+def _get_allign_args(
+    mol: "Molecule | Mol",
+    anchor_tup: AnchorTup,
+) -> Tuple[np.ndarray, int, int, Tuple[int, int, int], "None | float"]:
     if anchor_tup.kind == KindEnum.FIRST:
         idx_rot = idx_trans = anchor_tup.anchor_idx[0]
         xyz = mol.as_array() if isinstance(mol, Molecule) else rdmol_as_array(mol)
-        return xyz, idx_rot, idx_trans
+        return xyz, idx_rot, idx_trans, anchor_tup.anchor_idx[:3], anchor_tup.angle_offset
 
     # Reserve index `-1` for a dummy atom representing the mean position of all anchors
     if isinstance(mol, Molecule):
@@ -212,14 +215,22 @@ def _get_allign_args(mol: "Molecule | Mol", anchor_tup: AnchorTup) -> Tuple[np.n
         idx_trans = anchor_tup.anchor_idx[0]
     else:
         raise ValueError(f"Unknown anchor kind: {anchor_tup.kind!r}")
-    return xyz, idx_rot, idx_trans
+    return xyz, idx_rot, idx_trans, anchor_tup.anchor_idx[:3], anchor_tup.angle_offset
 
 
 def allign_axis(mol: Molecule) -> None:
     """Allign a molecule with the Cartesian X-axis; setting **anchor** as the origin."""
-    xyz, idx_rot, idx_trans = _get_allign_args(mol, mol.properties.anchor_tup)
-    rotmat = optimize_rotmat(xyz, idx_rot)
-    xyz = np.matmul(xyz, rotmat.T, out=xyz)
+    xyz, idx_rot, idx_trans, idx_angle, angle = _get_allign_args(mol, mol.properties.anchor_tup)
+    rotmat1 = optimize_rotmat(xyz, idx_rot)
+    xyz = np.matmul(xyz, rotmat1.T, out=xyz)
+
+    # Manually rotate the ligand by a user-specified amount
+    if angle is not None:
+        i, j, k = idx_angle
+        vec_perp = np.cross(xyz[j] - xyz[i], xyz[k] - xyz[j])
+        rotmat2 = axis_rotation_matrix(vec_perp, angle)
+        xyz = np.matmul(xyz, rotmat2.T, out=xyz)
+
     xyz -= xyz[idx_trans]
     mol.from_array(xyz.round(decimals=3))
 
@@ -574,9 +585,15 @@ def modified_minimum_scan_rdkit(ligand: Molecule, bond_tuple: Tuple[int, int]) -
     # Find the conformation with the optimal ligand vector
     cost_list = []
     for rdmol in rdmol_list:
-        xyz, idx_rot, idx_trans = _get_allign_args(rdmol, ligand.properties.anchor_tup)
+        xyz, idx_rot, idx_trans, idx_angle, angle = _get_allign_args(rdmol,
+                                                                     ligand.properties.anchor_tup)
         rotmat = optimize_rotmat(xyz, idx_rot)
         xyz = np.matmul(xyz, rotmat.T, out=xyz)
+        if angle is not None:
+            i, j, k = idx_angle
+            vec_perp = np.cross(xyz[j] - xyz[i], xyz[k] - xyz[j])
+            rotmat2 = axis_rotation_matrix(vec_perp, angle)
+            xyz = np.matmul(xyz, rotmat2.T, out=xyz)
         xyz -= xyz[idx_trans]
         cost = np.exp(xyz[:, 1:]).sum()
         cost_list.append(cost)
diff --git a/CAT/data_handling/anchor_parsing.py b/CAT/data_handling/anchor_parsing.py
index 2ebd0c07..9eec4ba2 100644
--- a/CAT/data_handling/anchor_parsing.py
+++ b/CAT/data_handling/anchor_parsing.py
@@ -1,9 +1,11 @@
 """A module for parsing the ``ligand.anchor`` keyword."""
 
+import re
 import operator
-from typing import Union, Tuple, Collection, Iterable
+from typing import Union, Tuple, Collection, Iterable, SupportsFloat
 
 from rdkit.Chem import Mol
+from scm.plams import Units, PT
 from schema import Schema, Use, Optional
 from typing_extensions import TypedDict, SupportsIndex
 
@@ -20,6 +22,24 @@ class _UnparsedAnchorDictBase(TypedDict):
 
 class _UnparsedAnchorDict(_UnparsedAnchorDictBase, total=False):
     remove: "None | SupportsIndex | Collection[SupportsIndex]"
+    angle_offset: "None | SupportsFloat | SupportsIndex | bytes | str"
+
+
+class _AnchorDict(TypedDict):
+    group: str
+    group_idx: Tuple[int, ...]
+    remove: "None | Tuple[int, ...]"
+    kind: KindEnum
+    angle_offset: "None | float"
+
+
+def _pt_sort_func(symbol: str) -> Tuple[int, str]:
+    return len(symbol), symbol
+
+
+_SYMBOL = "|".join(sorted(PT.symtonum, key=_pt_sort_func))
+_SYMBOL_PATTERN = re.compile(f"({_SYMBOL})")
+_UNIT_PATTERN = re.compile(r"([\.\_0-9]+)(\s+)?(\w+)?")
 
 
 def _parse_group_idx(item: "SupportsIndex | Iterable[SupportsIndex]") -> Tuple[int, ...]:
@@ -57,11 +77,32 @@ def _parse_kind(typ: "None | str | KindEnum") -> KindEnum:
         return KindEnum[typ.upper()]
 
 
+def _parse_angle_offset(
+    offset: "None | SupportsFloat | SupportsIndex | bytes | str"
+) -> "None | float":
+    """Parse the ``angle_offset`` option; convert the offset to radians."""
+    if offset is None:
+        return None
+    elif not isinstance(offset, str):
+        return Units.convert(float(offset), "deg", "rad")
+
+    # match offsets such as `"5.5 degree"`
+    match = _UNIT_PATTERN.match(offset)
+    if match is None:
+        raise ValueError(f"Invalid offset string: {offset!r}")
+
+    offset, _, unit = match.groups()
+    if unit is None:
+        unit = "deg"
+    return Units.convert(float(offset), unit, "rad")
+
+
 anchor_schema = Schema({
     "group": str,
-    "group_idx": Use(lambda i: tuple(_parse_group_idx(i))),
+    "group_idx": Use(_parse_group_idx),
     Optional("remove", default=None): Use(_parse_remove),
     Optional("kind", default=KindEnum.FIRST): Use(_parse_kind),
+    Optional("angle_offset", default=None): Use(_parse_angle_offset),
 })
 
 
@@ -83,7 +124,7 @@ def parse_anchors(
         patterns = [patterns]
 
     ret = []
-    for p in patterns:  # type: _UnparsedAnchorDict | str | Mol
+    for p in patterns:  # type: _UnparsedAnchorDict | str | Mol | AnchorTup
         if isinstance(p, AnchorTup):
             ret.append(p)
         elif isinstance(p, Mol):
@@ -96,12 +137,31 @@ def parse_anchors(
             remove = None if not split else (list(mol.GetAtoms())[-1].GetIdx(),)
             ret.append(AnchorTup(mol=mol, group=group, remove=remove))
         else:
-            kwargs = anchor_schema.validate(p)
+            kwargs: _AnchorDict = anchor_schema.validate(p)
+
+            # Check that `group_idx` and `remove` are disjoint
             group_idx = kwargs["group_idx"]
             remove = kwargs["remove"]
             if remove is not None and not set(group_idx).isdisjoint(remove):
                 raise ValueError("`group_idx` and `remove` must be disjoint")
 
-            mol = _smiles_to_rdmol(kwargs["group"])
+            # Check that the indices in `group_idx` and `remove` are not out of bounds
+            group = kwargs["group"]
+            symbols_list = _SYMBOL_PATTERN.findall(group)
+            if len(symbols_list) <= max(group_idx):
+                raise IndexError(f"`group_idx` index {max(group_idx)} is out of bounds "
+                                 f"for a `group` with {len(symbols_list)} atoms")
+            elif remove is not None and len(symbols_list) <= max(remove):
+                raise IndexError(f"`remove` index {max(remove)} is out of bounds "
+                                 f"for a `group` with {len(symbols_list)} atoms")
+
+            # Check that at least 3 atoms are available for `angle_offset`
+            # (so a plane can be defined)
+            angle_offset = kwargs["angle_offset"]
+            if angle_offset is not None and len(group_idx) < 3:
+                raise ValueError("`group_idx` must contain at least 3 atoms when "
+                                 "`angle_offset` is specified")
+
+            mol = _smiles_to_rdmol(group)
             ret.append(AnchorTup(**kwargs, mol=mol))
     return tuple(ret)
diff --git a/CAT/utils.py b/CAT/utils.py
index 2cbdd489..765e8005 100644
--- a/CAT/utils.py
+++ b/CAT/utils.py
@@ -550,3 +550,4 @@ class AnchorTup(NamedTuple):
     anchor_idx: Tuple[int, ...] = ()
     remove: "None | Tuple[int, ...]" = None
     kind: KindEnum = KindEnum.FIRST
+    angle_offset: "None | float" = None
diff --git a/CHANGELOG.rst b/CHANGELOG.rst
index 09c0f900..2b98b242 100644
--- a/CHANGELOG.rst
+++ b/CHANGELOG.rst
@@ -6,6 +6,11 @@ All notable changes to this project will be documented in this file.
 This project adheres to `Semantic Versioning <http://semver.org/>`_.
 
 
+0.10.1
+******
+* Added the option to manually specify angle offsets for the ligand vector.
+
+
 0.10.0
 ******
 * Add more advanced anchor-parsing options.
diff --git a/README.rst b/README.rst
index 3deecd3a..2461f1cc 100644
--- a/README.rst
+++ b/README.rst
@@ -17,7 +17,7 @@
    :target: https://docs.python.org/3.9/
 
 ###############################
-Compound Attachment Tool 0.10.0
+Compound Attachment Tool 0.10.1
 ###############################
 
 **CAT** is a collection of tools designed for the construction of various chemical compounds.
diff --git a/docs/4_optional.rst b/docs/4_optional.rst
index da4e0a91..111c9369 100644
--- a/docs/4_optional.rst
+++ b/docs/4_optional.rst
@@ -629,6 +629,7 @@ Ligand
         * :attr:`anchor.group_idx`
         * :attr:`anchor.remove`
         * :attr:`anchor.kind`
+        * :attr:`anchor.angle_offset`
 
         .. note::
 
@@ -675,9 +676,11 @@ Ligand
         .. note::
             This argument has no value be default and must thus be provided by the user.
 
+
     .. attribute:: optional.ligand.anchor.remove
 
         :Parameter:     * **Type** - :data:`None`, :class:`int` or :class:`Sequence[int] <collections.abc.Sequence>`
+                        * **Default value** – :data:`None`
 
         The indices of the to-be removed atoms in :attr:`anchor.group <optional.ligand.anchor.group>`.
 
@@ -689,6 +692,7 @@ Ligand
     .. attribute:: optional.ligand.anchor.kind
 
         :Parameter:     * **Type** - :class:`str`
+                        * **Default value** – ``"first"``
 
         How atoms are to-be attached when multiple anchor atoms are specified in :attr:`anchor.group_idx <optional.ligand.anchor.group_idx>`.
 
@@ -699,6 +703,19 @@ Ligand
         * ``"mean_translate"``: Attach the mean position of all anchoring atoms to the core and then translate back to the first atom.
 
 
+    .. attribute:: optional.ligand.anchor.angle_offset
+
+        :Parameter:     * **Type** - :data:`None`, :class:`float` or :class:`str`
+                        * **Default value** – :data:`None`
+
+        Manually offset the angle of the ligand vector by a given number.
+
+        The plane of rotation is defined by the first three indices in :attr:`anchor.group_idx <optional.ligand.anchor.group_idx>`.
+
+        By default the angle unit is assumed to be in degrees,
+        but if so desired one can explicitly pass the unit: ``angle_offset: "0.25 rad"``.
+
+
     .. attribute:: optional.ligand.split
 
         :Parameter:     * **Type** - :class:`bool`
diff --git a/docs/conf.py b/docs/conf.py
index 98d551a0..893e9d56 100755
--- a/docs/conf.py
+++ b/docs/conf.py
@@ -77,7 +77,7 @@
 
 # The version info for the project you're documenting, acts as replacement for
 # |version| and |release|, also used in various other places throughout the built documents.
-release = '0.10.0'  # The full version, including alpha/beta/rc tags.
+release = '0.10.1'  # The full version, including alpha/beta/rc tags.
 version = release.rsplit('.', maxsplit=1)[0]
 
 
diff --git a/tests/test_files/test_ligand_anchoring.hdf5 b/tests/test_files/test_ligand_anchoring.hdf5
index 9dbbf486..c7c52f24 100644
Binary files a/tests/test_files/test_ligand_anchoring.hdf5 and b/tests/test_files/test_ligand_anchoring.hdf5 differ
diff --git a/tests/test_ligand_anchoring.py b/tests/test_ligand_anchoring.py
index 2b45a393..4d5a6a3e 100644
--- a/tests/test_ligand_anchoring.py
+++ b/tests/test_ligand_anchoring.py
@@ -146,6 +146,7 @@ def get_h5py_file(self) -> Generator[h5py.Group, None, None]:
         "kind_first": dict(group="OC(=O)C", group_idx=0, kind="FIRST"),
         "kind_mean": dict(group="OC(=O)C", group_idx=[0, 2], kind="MEAN"),
         "kind_mean_translate": dict(group="OC(=O)C", group_idx=[0, 2], kind="MEAN_TRANSLATE"),
+        "angle": dict(group="OC(=O)C", group_idx=[0, 1, 2], angle_offset=45),
     })
 
     @pytest.mark.parametrize("kwargs_id,kwargs", OPTIONS_DICT.items(), ids=OPTIONS_DICT.keys())