<?xml version='1.0' encoding='UTF-8'?><codeBook xmlns="ddi:codebook:2_5" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="ddi:codebook:2_5 https://ddialliance.org/Specification/DDI-Codebook/2.5/XMLSchema/codebook.xsd" version="2.5"><docDscr><citation><titlStmt><titl>Experimental data for: Laboratory diffusion experiments with HTO, D2O, H218O, 36Cl-, Br-, I-, 79SeO42-, 22Na+, 85Sr2+, 133Ba2+ and 226Ra2+ in Opalinus Clay parallel to the bedding plane: experimental results and modelling</titl><IDNo agency="DOI">doi:10.26165/JUELICH-DATA/7Q3NQL</IDNo></titlStmt><distStmt><distrbtr source="archive">Jülich DATA</distrbtr><distDate>2025-11-18</distDate></distStmt><verStmt source="DVN"><version date="2026-03-13" type="RELEASED">2</version></verStmt><biblCit>Van Loon, L. R.; Glaus, M. A.; Brandt, Felix; Klinkenberg, Martina, 2025, "Experimental data for: Laboratory diffusion experiments with HTO, D2O, H218O, 36Cl-, Br-, I-, 79SeO42-, 22Na+, 85Sr2+, 133Ba2+ and 226Ra2+ in Opalinus Clay parallel to the bedding plane: experimental results and modelling", https://doi.org/10.26165/JUELICH-DATA/7Q3NQL, Jülich DATA, V2</biblCit></citation></docDscr><stdyDscr><citation><titlStmt><titl>Experimental data for: Laboratory diffusion experiments with HTO, D2O, H218O, 36Cl-, Br-, I-, 79SeO42-, 22Na+, 85Sr2+, 133Ba2+ and 226Ra2+ in Opalinus Clay parallel to the bedding plane: experimental results and modelling</titl><IDNo agency="DOI">doi:10.26165/JUELICH-DATA/7Q3NQL</IDNo></titlStmt><rspStmt><AuthEnty affiliation="Labor für Endlagersicherheit, Paul Scherrer Institut, 5232 Villigen PSI, Switzerland">Van Loon, L. R.</AuthEnty><AuthEnty affiliation="Labor für Endlagersicherheit, Paul Scherrer Institut, 5232 Villigen PSI, Switzerland">Glaus, M. A.</AuthEnty><AuthEnty affiliation="Institute of Fusion Energy and Nuclear Waste Management  – Nuclear Waste Management (IFN-2)">Brandt, Felix</AuthEnty><AuthEnty affiliation="Institute of Fusion Energy and Nuclear Waste Management  – Nuclear Waste Management (IFN-2)">Klinkenberg, Martina</AuthEnty></rspStmt><prodStmt/><distStmt><distrbtr source="archive">Jülich DATA</distrbtr><contact affiliation="Institute of Fusion Energy and Nuclear Waste Management  – Nuclear Waste Management (IFN-2)" email="m.klinkenberg@fz-juelich.de">Klinkenberg, Martina</contact><depositr>Klinkenberg, Martina</depositr><depDate>2025-09-16</depDate></distStmt></citation><stdyInfo><subject><keyword>Earth and Environmental Sciences</keyword></subject><abstract>The diffusion of a suite of tracers (stable isotope species and radiotracers) was studied in Opalinus Clay (OPA) samples originating from two different boreholes at the Mont Terri Underground Research Laboratory in Switzerland (BDR-2 and BMA-A1). This data publication includes Excel tables containing the raw data for the diffusion experiments presented and the corresponding modelling performed, as well as a PDF document with additional information and data that are not included in the main publication.</abstract><sumDscr/></stdyInfo><method><dataColl><sources/></dataColl><anlyInfo/></method><dataAccs><setAvail/><useStmt/></dataAccs><othrStdyMat/></stdyDscr><otherMat ID="f38722" URI="https://data.fz-juelich.de/api/access/datafile/38722" level="datafile"><labl>FZJ_Zelle7.xlsx</labl><notes level="file" type="DATAVERSE:CONTENTTYPE" subject="Content/MIME Type">application/vnd.openxmlformats-officedocument.spreadsheetml.sheet</notes></otherMat><otherMat ID="f38720" URI="https://data.fz-juelich.de/api/access/datafile/38720" level="datafile"><labl>FZJ_Zelle9.xlsx</labl><notes level="file" type="DATAVERSE:CONTENTTYPE" subject="Content/MIME Type">application/vnd.openxmlformats-officedocument.spreadsheetml.sheet</notes></otherMat><otherMat ID="f38716" URI="https://data.fz-juelich.de/api/access/datafile/38716" level="datafile"><labl>PSI_BDR2-1.xlsx</labl><notes level="file" type="DATAVERSE:CONTENTTYPE" subject="Content/MIME Type">application/vnd.openxmlformats-officedocument.spreadsheetml.sheet</notes></otherMat><otherMat ID="f38719" URI="https://data.fz-juelich.de/api/access/datafile/38719" level="datafile"><labl>PSI_BDR2-2.xlsx</labl><notes level="file" type="DATAVERSE:CONTENTTYPE" subject="Content/MIME Type">application/vnd.openxmlformats-officedocument.spreadsheetml.sheet</notes></otherMat><otherMat ID="f38718" URI="https://data.fz-juelich.de/api/access/datafile/38718" level="datafile"><labl>PSI_BDR2-3.xlsx</labl><notes level="file" type="DATAVERSE:CONTENTTYPE" subject="Content/MIME Type">application/vnd.openxmlformats-officedocument.spreadsheetml.sheet</notes></otherMat><otherMat ID="f38715" URI="https://data.fz-juelich.de/api/access/datafile/38715" level="datafile"><labl>PSI_BDR2-5.xlsx</labl><notes level="file" type="DATAVERSE:CONTENTTYPE" subject="Content/MIME Type">application/vnd.openxmlformats-officedocument.spreadsheetml.sheet</notes></otherMat><otherMat ID="f38721" URI="https://data.fz-juelich.de/api/access/datafile/38721" level="datafile"><labl>PSI_BDR2-6.xlsx</labl><notes level="file" type="DATAVERSE:CONTENTTYPE" subject="Content/MIME Type">application/vnd.openxmlformats-officedocument.spreadsheetml.sheet</notes></otherMat><otherMat ID="f48421" URI="https://data.fz-juelich.de/api/access/datafile/48421" level="datafile"><labl>Van Loon et al 2026 Supporting Information.pdf</labl><notes level="file" type="DATAVERSE:CONTENTTYPE" subject="Content/MIME Type">application/pdf</notes></otherMat></codeBook>