diff --git a/.zenodo.json b/.zenodo.json
new file mode 100644
index 0000000..e59a789
--- /dev/null
+++ b/.zenodo.json
@@ -0,0 +1,80 @@
+{
+ "creators": [
+ {
+ "orcid": "0000-0001-6583-2148",
+ "affiliation": "Pharmaceutical Sciences, University of California Irvine, Irvine, CA, USA",
+ "name": "Behara, Pavan Kumar"
+ },
+ {
+ "orcid": "0000-0001-7856-1156",
+ "affiliation": "Department of Chemistry, University of California Irvine, Irvine, CA, USA",
+ "name": "Gokey, Trevor"
+ },
+ {
+ "orcid": "0000-0002-5899-7953",
+ "affiliation": "Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, CA, USA",
+ "name": "Cavender, Chapin"
+ },
+ {
+ "orcid": "0000-0001-8694-7200",
+ "affiliation": "School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne NE1, 7RU, United Kingdom",
+ "name": "Horton, Joshua"
+ },
+ {
+ "orcid": "0000-0002-6095-6704",
+ "affiliation": "Open Force Field Consortium, Open Molecular Software Foundation, Davis, CA, USA",
+ "name": "Wang, Lily"
+ },
+ {
+ "orcid": "0000-0002-1697-2918",
+ "affiliation": "Department of Chemistry, University of California Davis, Davis, CA, USA",
+ "name": "Jang, Hyesu"
+ },
+ {
+ "orcid": "0000-0001-6448-0873",
+ "affiliation": "Open Force Field Consortium, Open Molecular Software Foundation, Davis, CA, USA",
+ "name": "Wagner, Jeffrey"
+ },
+ {
+ "orcid": "0000-0003-2933-0719",
+ "affiliation": "School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne NE1, 7RU, United Kingdom",
+ "name": "Cole, Daniel"
+ },
+ {
+ "orcid": "0000-0001-9145-6457",
+ "affiliation": "OpenEye Scientific Software, Santa Fe, NM, USA",
+ "name": "Bayly, Christopher"
+ },
+ {
+ "orcid": "0000-0002-1083-5533",
+ "affiliation": "Pharmaceutical Sciences, University of California Irvine, Irvine, CA, USA",
+ "name": "Mobley, David"
+ }
+ ],
+ "access_right": "open",
+ "resource_type": {
+ "type": "software",
+ "title": "Software"
+ },
+ "related_identifiers": [
+ {
+ "scheme": "doi",
+ "identifier": "10.5281/zenodo.5214478",
+ "relation": "isVersionOf"
+ }
+ ],
+
+ "license": "CC-BY-4.0",
+ "title": "openforcefield/openff-forcefields",
+
+ "communities": [
+ {
+ "id": "openforcefield"
+ }
+ ],
+ "keywords": [
+ "force field",
+ "molecular dynamics",
+ "openforcefield"
+ ]
+}
diff --git a/README.md b/README.md
index e54ccd6..02e00c0 100644
--- a/README.md
+++ b/README.md
@@ -26,12 +26,14 @@ Details for each force field in this repository can be found in the following ta
| Filename | DOI | FF line | Release Date | Major format changes? |
|---------------------------------------------|-----------------------------------------------------------------------------------------------------------|---------|---------------|-----------------------|
+| `openff-2.1.0-rc.1.offxml` | | Sage | Apr 10, 2023 | No |
+| `openff_unconstrained-2.1.0-rc.1.offxml` | | Sage | Apr 10, 2023 | No |
| `tip3p_fb-1.0.0.offxml` | see `docs/water-models.md` | Ports | Feb 27, 2023 | No |
| `tip3p-1.0.0.offxml` | see `docs/water-models.md` | Ports | Feb 27, 2023 | No |
| `openff-2.0.0.offxml` | [](https://doi.org/10.5281/zenodo.5214478) | Sage | Aug 16, 2021 | No |
| `openff_unconstrained-2.0.0.offxml` | [](https://doi.org/10.5281/zenodo.5214478) | Sage | Aug 16, 2021 | No |
| `openff-2.0.0-rc.2.offxml` | [](https://doi.org/10.5281/zenodo.5156698) | Sage | Aug 3, 2021 | No |
-| `openff_unconstrained-2.0.0-rc.2.offxml` | [](https://doi.org/10.5281/zenodo.5156698) | Sage | Aug 3, 2021 | No |
+ | `openff_unconstrained-2.0.0-rc.2.offxml` | [](https://doi.org/10.5281/zenodo.5156698) | Sage | Aug 3, 2021 | No |
| `openff-2.0.0-rc.1.offxml` | [](https://doi.org/10.5281/zenodo.5009196) | Sage | June 21, 2021 | No |
| `openff_unconstrained-2.0.0-rc.1.offxml` | [](https://doi.org/10.5281/zenodo.5009196) | Sage | June 21, 2021 | No |
| `openff-1.3.1.offxml` | [](https://doi.org/10.5281/zenodo.5009058) | Parsley | June 21, 2021 | No |
diff --git a/openforcefields/offxml/openff-2.1.0-rc.1.offxml b/openforcefields/offxml/openff-2.1.0-rc.1.offxml
new file mode 100644
index 0000000..433e681
--- /dev/null
+++ b/openforcefields/offxml/openff-2.1.0-rc.1.offxml
@@ -0,0 +1,392 @@
+
+
+ The Open Force Field Initiative
+ 2023-04-10
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diff --git a/openforcefields/offxml/openff_unconstrained-2.1.0-rc.1.offxml b/openforcefields/offxml/openff_unconstrained-2.1.0-rc.1.offxml
new file mode 100644
index 0000000..6336d37
--- /dev/null
+++ b/openforcefields/offxml/openff_unconstrained-2.1.0-rc.1.offxml
@@ -0,0 +1,391 @@
+
+
+ The Open Force Field Initiative
+ 2023-04-10
+
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