public string LabelDataMember { get; set; }

Public Property LabelDataMember As String

<dxtm:SunburstControl>
    <dxtm:SunburstControl.DataAdapter>
        <dxtm:SunburstFlatDataAdapter
            x:Name="dataAdapter"
            LabelDataMember="Symbol"
            ValueDataMember="Value"
            DataSource="{Binding}"
            GroupDataMembers="Block, Family"/>
    </dxtm:SunburstControl.DataAdapter>
</dxtm:SunburstControl>

using System;
using System.Collections.Generic;
using System.IO;
using System.Windows;
using System.Xml;
using System.Xml.Linq;

namespace SunburstSample {
    public partial class MainWindow : Window {
        public MainWindow() {
            InitializeComponent();
            DataContext = LoadDataFromXML();
        }
        List<ChemicalElement> LoadDataFromXML() {
            XDocument document = XDocument.Load(@"D:\ChemicalElements.xml");
            List<ChemicalElement> infos = new List<ChemicalElement>();
            if (document != null) {
                foreach (XElement element in document.Element("ArrayOfElement").Elements()) {
                    ChemicalElement chemicalElement = new ChemicalElement();
                    chemicalElement.Name = element.Element("Name").Value;
                    chemicalElement.AtomicMass = element.Element("AtomicMass").Value;
                    chemicalElement.AtomicNumber = element.Element("AtomicNumber").Value;
                    chemicalElement.Density = element.Element("Density").Value;
                    chemicalElement.MeltingPoint = element.Element("MeltingPoint").Value;
                    chemicalElement.BoilingPoint = element.Element("BoilingPoint").Value;
                    chemicalElement.Block = element.Element("Block").Value;
                    chemicalElement.Family = element.Element("Family").Value;
                    chemicalElement.Symbol = element.Element("Symbol").Value;
                    infos.Add(chemicalElement);
                }
            }
            return infos;
        }
    }
    public static class DataLoader {
        static Stream GetStream(string fileName) {
            Uri uri = GetResourceUri(fileName);
            return Application.GetResourceStream(uri).Stream;
        }
        public static Uri GetResourceUri(string fileName) {
            return new Uri(fileName, UriKind.RelativeOrAbsolute);
        }
        public static XDocument LoadXDocumentFromResources(string fileName) {
            try {
                return XDocument.Load(GetStream(fileName));
            }
            catch {
                return null;
            }
        }
    }
    public class ChemicalElement {
        public string AtomicNumber { get; set; }
        public string AtomicMass { get; set; }
        public string Density { get; set; }
        public string MeltingPoint { get; set; }
        public string BoilingPoint { get; set; }
        public string Name { get; set; }
        public string Block { get; set; }
        public string Family { get; set; }
        public string Symbol { get; set; }
        public int Value { get { return 1; } }
    }
}

Imports System
Imports System.Collections.Generic
Imports System.IO
Imports System.Xml.Linq
Namespace SunburstSample
    Public Partial Class MainWindow
        Inherits Window
        Public Sub New()
            InitializeComponent()
            DataContext = LoadDataFromXML()
        End Sub
        Private Function LoadDataFromXML() As List(Of ChemicalElement)
            Dim document As XDocument = XDocument.Load("D:\ChemicalElements.xml")
            Dim infos As List(Of ChemicalElement) = New List(Of ChemicalElement)()
            If document IsNot Nothing Then
                For Each element As XElement In document.Element("ArrayOfElement").Elements()
                    Dim chemicalElement As ChemicalElement = New ChemicalElement()
                    chemicalElement.Name = element.Element("Name").Value
                    chemicalElement.AtomicMass = element.Element("AtomicMass").Value
                    chemicalElement.AtomicNumber = element.Element("AtomicNumber").Value
                    chemicalElement.Density = element.Element("Density").Value
                    chemicalElement.MeltingPoint = element.Element("MeltingPoint").Value
                    chemicalElement.BoilingPoint = element.Element("BoilingPoint").Value
                    chemicalElement.Block = element.Element("Block").Value
                    chemicalElement.Family = element.Element("Family").Value
                    chemicalElement.Symbol = element.Element("Symbol").Value
                    infos.Add(chemicalElement)
                Next
            End If
            Return infos
        End Function
    End Class
    Public Module DataLoader
        Private Function GetStream(ByVal fileName As String) As Stream
            Dim uri As Uri = GetResourceUri(fileName)
            Return Application.GetResourceStream(uri).Stream
        End Function
        Public Function GetResourceUri(ByVal fileName As String) As Uri
            Return New Uri(fileName, UriKind.RelativeOrAbsolute)
        End Function
        Public Function LoadXDocumentFromResources(ByVal fileName As String) As XDocument
            Try
                Return XDocument.Load(GetStream(fileName))
            Catch
                Return Nothing
            End Try
        End Function
    End Module
    Public Class ChemicalElement
        Public Property AtomicNumber As String
        Public Property AtomicMass As String
        Public Property Density As String
        Public Property MeltingPoint As String
        Public Property BoilingPoint As String
        Public Property Name As String
        Public Property Block As String
        Public Property Family As String
        Public Property Symbol As String
        Public ReadOnly Property Value As Integer
            Get
                Return 1
            End Get
        End Property
    End Class
End Namespace

<?xml version="1.0"?>
<ArrayOfElement xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
  <Element>
    <FakeValue>1</FakeValue>
    <AtomicNumber>1</AtomicNumber>
    <Group>1</Group>
    <Period>1</Period>
    <Symbol>H</Symbol>
    <Name>Hydrogen</Name>
    <AtomicMass>1.008</AtomicMass>
    <Density>0.00008988</Density>
    <MeltingPoint>14.01</MeltingPoint>
    <BoilingPoint>20.28</BoilingPoint>
    <Family>Nonmetal</Family>
    <DiscoveryPeriod>Middle Ages–​1799</DiscoveryPeriod>
    <Block>S-block</Block>
  </Element>
  <!--...-->
</ArrayOfElement>